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VOL,  XXXII 


I7  JAN  IS  1924 


NO.  5 


PSYCHOLOGICAL  REVIEW  PUBLICATIONS 


WHOLE  NO.  I47 

1923 


Psychological  Monographs 


EDITED  BY 

JAMES  ROWLAND  ANGELL,  Yale  University 
HOWARD  C.  WARREN,  Princeton  University  ( Review ) 

JOHN  B.  WATSON,  New  York  (/.  of  Exp.  Psychol.) 

SHEPHERD  I.  FRANZ,  Govt.  Hosp.  for  Insane  ( Bulletin )  and 
MADISON  BENTLEY,  University  of  Illinois  (Index) 


STUDIES  FROM  THE  PSYCHOLOGICAL  LABORATORY 
OF  THE  UNIVERSITY  OF  CHICAGO 


The  Influ  ence  ofMechanical  Guidance 


Maze  Learning 


BV 

HELEN  LOIS  KOCH,  Ph.D. 


Instructor  in  Educational  Psychology  in  the  University  of  Texas 


PSYCHOLOGICAL  REVIEW  COMPANY 

PRINCETON,  N.vJ. 

Agents:  G.  E.  STECHERT  &  CO.,  London  (2  Star  Yard,  Carey  St.,  W.  C.) 

Paris  (16  rue  de  Conde) 


ACKNOWLEDGMENTS 


The  writer  wishes  to  express  her  deep  gratitude  to  Professor 
Harvey  A.  Carr  for  his  untiring  and  critical  supervision  of  this 
research,  as  well  as  for  the  innumerable  other  kindnesses  shown 
her.  To  President  James  Rowland  Angell,  Professor  C.  Judson 
Herrick  and  Professor  J.  R.  Kantor  she  is  indebted  for  much 
inspiration  and  guidance. 


CONTENTS 


PAGE 

I.  Introduction  .  i 

II.  The  Relative  Efficacy  of  Control  Introduced  at 

Various  Positions  in  the  Learning  Process .  n 

A.  Results  Based  upon  the  Records  of  Animal  Subjects  13 

1.  Influence  of  Two  Directed  Trials  Introduced 

at  Various  Positions  in  the  Learning  Process.  13 

2.  Influence  of  Four  Directed  Trials  Introduced 

at  Various  Positions  in  the  Learning  Process.  22 

3.  Influence  of  Six  Directed  Trials  Introduced 

at  Various  Positions  in  the  Learning  Process.  28 

4.  Influence  of  Eight  Directed  Trials  Introduced 

at  Various  Positions  in  the  Learning  Process.  34 

B.  Results  Based  upon  the  Records  of  Human  Subjects  38 

1.  Influence  of  Two  Directed  Trials  Introduced 

at  Various  Positions  in  the  Learning  Process.  38 

2.  Influence  of  Four  Directed  Trials  Introduced 

at  Various  Positions  in  the  Learning  Process.  46 

3.  Influence  of  Six  Directed  Trials  Introduced 

at  Various  Positions  in  the  Learning  Process.  52 

4.  Influence  of  Eight  Directed  Trials  Introduced 

at  Various  Positions  in  the  Learning  Process.  57 

III.  The  Relative  Efficacy  of  Various  Amounts  of 

Control  .  67 

A.  Results  Based  upon  the  Records  of  Animal  Subjects  67 

1.  Influence  of  Various  Amounts  of  Initial  Guid¬ 
ance  .  67 

2.  Influence  of  Various  Amounts  of  Guidance 

Introduced  upon  the  Fifth  Trial .  72 

B.  Results  Based  upon  the  Records  of  Human  Subjects  75 

1.  Influence  of  Various  Amounts  of  Initial  Guid¬ 
ance  .  75 

v 


VI 


CONTENTS 


PAGE 


2.  Influence  of  Various  Amounts  of  Guidance 

Introduced  upon  the  Fifth  Trial .  80 

3.  Influence  of  Various  Amounts  of  Guidance 

Introduced  upon  the  Seventh  Trial .  83 

4.  Influence  of  Various  Amounts  of  Guidance 

Introduced  upon  the  Ninth  Trial .  86 

IV.  The  Influence  of  Control  upon  Retention .  93 

V.  The  Influence  of  Guided  Learning  upon  the  Adapt¬ 
ability  of  the  Learned  Reaction .  98 

VI.  General  Summary  .  106 


I 


INTRODUCTION 

The  general  purport  of  this  study  is  an  investigation  of  the  in¬ 
fluence  upon  maze  learning  of  the  mechanical  prevention  of  error. 

The  research  was  carried  on  in  the  years  1919-1920  at  the 
Psychological  Laboratory  of  the  University  of  Chicago  and  was 
a  direct  outgrowth  of  an  investigation  conducted  jointly  by  Dr. 
H.  A.  Carr  and  the  author,1  in  which  an  attempt  was  made  to 
train  some  albino  rats  to  do  a  task  by  guiding  them  for  a  time 
through  the  critical  phase  of  the  situation.  The  guidance  was 
mechanical  in  its  nature,  and,  while  conducting  the  animal  through 
the  proper  response,  it  still  permitted  him  to  initiate  all  of  his 
activities.  The  problem  to  be  mastered  was  the  alternate  choice 
of  the  right  and  left  paths  of  a  T-shaped  problem  box  in  each 
day’s  test  of  ten  successive  runs.  The  results  revealed  that  the 
group  of  animals  which  was  guided  forty  out  of  every  fifty  trials 
did  not  react  to  the  situation  so  effectively  as  did  the  unguided 
group.  The  control  was  not,  however,  without  marked  positive 
effect  upon  some  of  the  animals. 

The  maze  problem  was  selected  as  the  medium  for  the  present 
investigation  for  the  following  reasons  :  ( 1 )  In  so  far  as  the  maze 
differs  from  the  problem  box  just  described,  its  employment  will 
cast  some  light  upon  the  question  of  the  relation  between  the  na¬ 
ture  of  the  problem  and  the  effectiveness  of  control.  (2)  The  maze 
problem  is  an  eliminative  type  of  problem;  that  is,  its  mastery  in¬ 
volves  primarily  the  elimination  of  error,  rather  than  the  acquisi¬ 
tion  of  any  new  movement.  It  is  reasonable  to  expect  that  control 
which  consists  of  the  prevention  of  errors  will  have  a  greater  in¬ 
fluence  upon  the  learning  of  such  a  problem  than  upon  the  learn¬ 
ing  of  those  in  whose  mastery  sheer  elimination  of  errors  plays  a 
less  dominant  role.  (3)  The  character  of  the  problem  is  such, 
furthermore,  that  it  permits  a  more  detailed  analysis  of  the  learn¬ 
ing  process  and  of  the  nature  of  the  effect  of  the  control  than 

1  “The  Influence  of  Extraneous  Controls  in  the  Learning  Process,”  Psych . 
Rev.,  vol.  26  (1919),  p.  287  ff. 


1 


2 


HELEN  LOIS  KOCH 


does  the  problem  box  hitherto  employed.  (4)  The  maze  presents 
a  problem  which  is  well  adapted  to  the  capacities  of  both  human 
subjects  and  rats,  and  thus  makes  possible  a  comparative  study  of 
the  influence  of  control  upon  these  widely  divergent  animal 
groups. 

Our  general  method  of  procedure  consisted  in  preventing  cul- 
de-sac  errors  in  certain  periods  of  the  learning,  by  blocking  the 
entrances  to  the  blind  alleys.  The  guiding  device  was  mechanical 
and,  hence,  subject  to  little  variation.  The  subject,  moreover,  was 
permitted  to  initiate  all  of  his  movements.  In  this  respect  our 
method  of  control  diverges  from  that  method  frequently  employed, 
in  which  the  subject,  who  is  supposedly  passive,  is  guided  by  the 
experimenter  through  the  movements  of  the  act  to  be  learned.  The 
influence  of  this  form  of  control  has  been  investigated  by  Thorn¬ 
dike,2  Cole,3  Yerkes,4  Hunter5  and  Ludgate.6 

The  problems  upon  which  the  present  study  will  attempt  to 
cast  light  are  the  following:  (1)  Does  the  mechanical  prevention 
of  errors  during  part  of  the  learning  process  have  any  influence 
upon  learning?  (2)  Does  the  efficacy  of  the  control  vary  with  the 
period  of  the  learning  at  which  it  is  administered?  A  comparison, 
for  instance,  of  the  relative  effectiveness  of  guidance  given  in  the 
initial  four  trials,  as  opposed  to  control  given  in  the  trials  from 
the  ninth  to  the  twelfth  inclusive,  will  furnish  significant  data  in 
regard  to  this  problem.  (3)  Is  the  efficacy  of  guidance  a  function 
of  the  amount  given?  Our  general  method  of  investigating  this 
problem  is  to  consider,  for  example,  the  relative  effectiveness  of 
two,  four  or  six,  etc.,  directed  trials,  interpolated  in  the  same 
general  position  in  the  learning  process.  (4)  Does  guidance  have  a 
similar  influence  upon  human  and  animal  subjects?  (5) Does  the 
fact  of  guidance  in  the  learning  period  have  any  influence  upon 

2  “Animal  Intelligence,”  Psych.  Rev.  Mon.  Suppl.,  vol.  2  (1898). 

3  “Concerning  the  Intelligence  of  Raccoons,”  Jour,  of  Comp.  Neur.  and 
Psych.,  vol.  1 7  (1907),  p.  21 1  ff. 

4  “The  Dancing  Mouse,”  (1907),  p.  201  ff. 

5  “A  Note  on  the  Behaviour  of  the  White  Rat,”  Jour,  of  Animal  Behav.,  vol. 
2  (1912),  p.  137  ff. 

6  “The  Effect  of  Manual  Guidance  upon  Maze  Learning,”  Psych.  Rev.  Mon. 
Suppl.,  vol.  33  (1923). 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


3 


the  retention  of  the  habit?  To  state  the  problem  more  simply: 
Does  a  subject  who  has  been  guided  during  the  learning  of  a 
problem  retain  the  habit  as  well  as  the  subject  who  has  not  been 
so  guided?  (6)  Does  the  fact  of  guidance  in  the  learning  period 
affect  the  stability  of  the  habit?  In  other  words,  is  an  individual 
who  has  mastered  the  problem  with  the  aid  of  guidance  as  likely 
to  be  confused  when  circumstances  are  slightly  altered  as  is  the 
individual  who  has  learned  the  problem  without  extraneous  con¬ 
trol? 

The  maze  used  in  the  experimentation  upon  the  animals  was 
constructed  of  oak  boards,  YY'  in  thickness.  It  was  supported  by  a 
wooden  frame  18"  high  and  was  4/x3'8"x6//  in  size.  The  pattern 
of  the  maze  is  indicated  in  Fig.  1.  The  runways  and  the  cul-de-sacs 


were  4"  wide.  The  partitions  within  the  maze,  which  were  made 
of  thin  sheets  of  galvanized  iron,  were  held  in  place  by  brass  sup¬ 
ports.  The  wood  and  metal  parts  of  the  apparatus  were  painted 
dull  black.  A  glass  cover  permitted  observation  of  all  of  the 
maneuverings  of  the  animal  while  he  was  in  the  runways.  The 
doors  that  opened  into  and  out  of  the  uncovered  food-box  were 
sliding  doors  which,  with  a  little  care,  could  be  closed  without 
distracting  the  animal  to  any  considerable  degree. 

The  blind  alleys  were  closed  off,  when  desired,  by  pieces  of 


4 


HELEN  LOIS  KOCH 


window  glass.  Attached  to  the  upper  edge  of  each  plate  of  glass 
was  a  blackened  brass  clamp  which,  when  sunk  into  the  sockets  in 
the  walls  of  the  alleys,  held  the  glass  partition  securely  in  place. 
The  glass  controls  were  not  set  in  flush  with  the  walls  of  the  main 
pathway,  but  rather  at  a  distance  of  three  centimeters  from  the 
ends  of  the  cul-de-sacs.  This  arrangement  was  adopted  in  order  to 
avoid,  as  far  as  possible,  the  distraction  from  the  alteration  of 
tactual  cues  which  one  would  expect  to  attend  the  introduction 
and  removal  of  the  controls.  Glass,  moreover,  rather  than  metal 
partitions,  were  employed,  in  order  to  reduce  to  a  minimum  the 
visual  distraction,  which  the  introduction  and  abstraction  of  the 
control  might  produce. 

After  some  preliminary  experimentation,  the  results  of  which 
indicated  that  directed  trials  occurring  subsequent  to  the  twelfth 
have  a  marked  deleterious  effect,  it  was  decided  to  concentrate 
within  the  first  twelve  trials  whatever  guidance  was  given  the 
animals. 

Series  of  two,  four,  six  or  eight  guided  trials  were,  with  one 
exception,  inserted  in  various  positions  within  the  first  twelve 
trials  involved  in  the  learning  of  the  maze.  A  series  of  two  suc¬ 
cessive  guided  trials  was  introduced,  in  the  case  of  one  group  of 
animals,  upon  the  first  run;  in  the  case  of  another,  upon  the  sixth 
run;  and  for  a  third  group,  upon  the  eleventh  run.  Four  groups  of 
animals  were  granted  a  period  of  control,  extending  over  four 
successive  trials.  The  period  of  guidance  began  with  the  first, 
fifth,  ninth  or  thirteenth  trial,  respectively.  Series  of  six  directed 
trials  were  employed,  in  the  case  of  three  groups  of  animals,  the 
introduction  of  the  directed  series  occurring  upon  the  first,  fourth 
or  seventh  trial,  respectively.  Successions  of  eight  guided  trials, 
commencing  upon  the  first,  third  or  fifth  run  of  the  learning  pe¬ 
riod,  respectively,  were  likewise  employed.  One  group  of  animals 
was  given  twelve  successive  directed  trials.  The  normal  group,  of 
course,  learned  the  maze  without  assistance.  It  is  evident  from  the 
schema  just  described  that  each  group  of  animals  received  either 
two,  four,  six  or  eight  guided  runs  at  either  the  beginning,  middle 
or  end  of  the  first  twelve  trials.  Such  a  grouping  enables  one  to 
compare  the  relative  effect  of  various  amounts  of  guidance,  as 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


5 


well  as  the  effect  of  the  position  of  the  guided  trials  upon  learn¬ 
ing. 

Sixteen  groups  of  ten  animals  each  were  employed  in  the  course 
of  the  experiment,  each  group  consisting,  because  of  the  scarcity 
of  females,  of  six  males  and  four  females.  The  rats  were  from 
seven  to  twelve  weeks  old.  Any  marked  biasing  of  the  results, 
through  differences  in  the  strain  of  the  animals  used,  was  avoided 
by  drawing  each  group  from  no  less  than  three  different  litters. 

The  rats  were  carefully  tamed  and  fed  in  the  food-box  of  the 
maze  for  one  week  before  training  was  begun.  Whatever  physical 
mutilation  of  the  animal  was  necessary  for  purposes  of  identifica¬ 
tion  was  effected  at  least  three  days  before  training  commenced. 
The  position  of  the  maze  was  never  changed  during  the  learning 
period  of  any  group  of  animals.  Lighting  conditions  were  con¬ 
trolled  as  far  as  possible.  The  shades  were  drawn  and  the  electric 
light  switched  on  before  work  was  begun.  The  experiment  was 
conducted  in  the  late  morning  and  early  afternoon  hours.  The 
cleaning  of  the  cages  and  replenishing  of  the  water  supply,  etc., 
was  cared  for  after  the  day’s  trials.  Thus,  for  the  accomplishment 
of  any  necessary  adjustments  to  the  slight  alterations  in  the  en¬ 
vironment,  a  period  of  twenty-four  hours  was  allowed.  The  same 
general  position  of  the  living  cage  of  any  group  of  animals  was 
maintained  throughout  the  entire  experiment. 

The  animals  were  kept  normally  hungry.  They  were  allowed  to 
feed  seven  minutes  per  day  on  bread  and  milk,  were  fed  on  an 
average  six  sunflower  seeds  per  individual  per  day,  and  once  a 
week  were  favored  with  a  small  piece  of  lettuce  or  apple.  One  bite 
of  food  before  each  run  served  to  stimulate  the  proper  incentive. 
The  animals  of  each  group  were  fed  together  at  the  end  of  the 
daily  experimentation. 

During  the  first  four  days,  each  rat  was  granted  only  one  trial 
per  day.  Thereafter,  however,  it  was  given  two  trials  per  day 
until  it  succeeded  in  making  four  perfect  runs  out  of  five  suc¬ 
cessive  attempts.  This  criterion  of  mastery  has  previously  been 
successfully  employed.7  No  record  of  the  distance  traversed  was 

7  Cf.  Webb :  “Transfer  of  Training  and  Retroaction,”  Psych.  Rev.  Mon. 
Suppl.,  vol.  24  (1917). 


6 


HELEN  LOIS  KOCH 


kept,  as  Miss  Hicks8  suggests;  but  the  method  of  counting  errors 
obviated  to  a  large  degree  many  of  the  difficulties  she  discusses. 
Any  return  over  a  whole  or  a  part  of  a  unit  of  the  true  pathway 
was  counted  as  a  return  error.  A  unit  of  the  true  pathway,  to  be 
explicit,  consists  of  a  section  of  the  runway  between  two  suc¬ 
cessive  turns  of  the  true  path,  irrespective  of  the  length  of  the 
section.  Every  entrance  into  a  cul-de-sac,  as  well  as  every  re¬ 
tracing  toward  the  end  of  the  cul-de-sac,  after  the  animal  had 
headed  toward  the  entrance,  was  considered  a  cul-de-sac  error. 

Time,  measured  by  a  stop  watch,  was  recorded  from  the  moment 
the  rat  left  the  entrance  until  its  whole  body,  with  the  exception  of 
its  tail,  was  brought  within  the  food-box. 

The  maze  employed  in  the  experiment  upon  human  subjects  was 
a  small  stylus  maze  of  the  same  general  design  as  the  maze  used 
for  the  rats.  The  cul-de-sacs  and  the  true  pathway,  which  were 
milled  out  of  a  solid  aluminum  casting,  were  y 4"  wide  and 
deep.  The  partitions  between  these  wedges  were,  likewise,  J4" 
thick.  The  outside  dimensions  of  the  maze  were  5^4"  x  5%". 
Small  brass  blocks,  from  the  bottom  of  which  projected  pegs  that 
could  be  inserted  into  small  holes  drilled  into  the  floor  of  the 
maze,  were  used  to  block  off  the  blind  alleys  in  the  directed  trials. 
The  blocks  were  inserted  at  the  same  relative  distance  from  the 
end  of  the  cul-de-sacs  as  were  the  glass  controls  in  the  maze  used 
in  the  experimentation  upon  animals.  The  absolute  distance  was 

3  /  // 

/  16  • 

The  maze  was  concealed  under  a  heavy  black  curtain  that  cov¬ 
ered  the  top  and  three  sides  of  a  supporting  wooden  frame.  The 
frame  was  ft.  wide,  1  ft.  deep,  and  1  ft.  high  on  the  side 
toward  the  subject,  whereas  it  was  ij4  ft.  high  on  the  side  ex¬ 
posed  to  the  experimenter.  From  that  side  of  the  frame  which  was 
uncovered,  the  experimenter  could  observe  the  progress  of  the 
subject.  In  order  to  prevent  any  distracting  movement,  the  maze 
was  held  tightly  in  place  by  a  small  wooden  frame  which  was 
nailed  to  the  table.  The  black  cloth  was  hung  loosely  enough  on 
the  side  toward  the  subject  so  that  his  arms  could  be  easily  in- 

8  “The  Relative  Value  of  the  Different  Curves  of  Learning,”  Jour,  of  An¬ 
imal  Bchav.,  vol.  I,  (1911),  p.  138  ff. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


7 


serted  under  it.  Such  an  apparatus  eliminates  the  disconcerting  ef¬ 
fect  of  blindfolding  and  reduces  the  problem  largely  to  a  tactual 
kinaesthetic-motor  level. 

The  subjects  were  required  to  trace  the  maze  with  a  hard  rubber 
stylus,  the  lower  end  of  which  was  3/i6"  in  diameter  and  could  be 
guided  easily  through  the  runways.  A  small  rubber  shield  5Ae" 
from  the  end  of  the  stylus  prevented  the  fingers  of  the  subject 
from  coming  in  contact  with  the  maze.  For  both  human  and  animal 
subjects  the  same  criterion  of  mastery  was  employed. 

The  subject  was  seated  at  a  table  and  the  following  written 
directions  were  given  to  him :  “Please  put  your  right  hand  under 
the  cover.  Grasp  the  stylus  and  hold  it  as  erect  as  possible.  Be  sure 
that  neither  your  fingers  nor  your  hand  touches  the  base  of  the 
apparatus.  Keep  the  stylus  in  the  groove  and  explore  the  assigned 
area  until  you  are  told  to  stop.  Use  any  method  you  desire.  The 
aim  of  the  experiment  is  to  find  the  shortest  possible  route  through 
the  maze.”  When  the  subject  placed  his  hand  under  the  cover,  the 
experimenter  put  the  stylus  in  it  and  placed  the  stylus  in  the  groove 
at  the  entrance  to  the  maze.  Then  the  experimenter  said  to  the 
subject,  “Now  you  are  in  the  groove.  Explore  the  maze  and  I  shall 
tell  you  when  you  reach  the  goal.”  When  the  subject  reached  the 
goal  for  the  first  time,  the  experimenter  said  to  him,  “Now  you 
have  reached  the  goal.  The  aim  of  the  experiment  is  to  learn  to 
reach  this  goal  without  taking  any  unnecessary  steps.”  The  object 
of  giving  instructions  to  the  subject  thus  piecemeal  is  to  avoid 
confusing  him  with  a  large  number  of  directions,  the  meaning  of 
which  can  only  become  apparent  when  he  has  had  some  experience 
with  the  situation.  The  repetition  in  various  forms  of  the  aim  of 
the  experiment  is  necessary  in  order  that  each  subject  may  thor¬ 
oughly  comprehend  what  is  desired  of  him.  Such  a  procedure  as 
Webb’s,9  in  which  the  subject  was  forced  to  deduce  the  aim  of  the 
experiment,  is  wholly  undesirable.  Webb  asserts  that  because  the 
human  subject  is  blindfolded  and  is  obliged  to  fathom  the  desires 
of  the  experimenter,  his  incentive  is  similar  to  that  of  the  rat 
who  is  placed  in  the  maze  and  allowed  to  seek  his  own  deliverance. 
Upon  a  close  scrutiny  of  the  situation  and  the  behavior  of  the  sub- 


9  Op.  cit.,  p.  14. 


8 


HELEN  LOIS  KOCH 


jects,  the  similarity  is  not  so  evident.  The  human  subject  does, 
from  the  first,  set  for  himself  a  problem.  The  problem,  if  the  sub¬ 
ject  is  not  instructed,  differs  with  each  individual.  Some  subjects 
believe  that  the  problem  is  to  traverse  every  inch  of  the  maze, 
rather  than  to  find  the  shortest  route.  The  rat,  we  assume,  moves 
through  the  maze  at  first  through  sheer  curiosity  and  inability  to 
be  quiet  unless  fatigued,  ill,  asleep  or  in  danger.  After  the  first 
few  trials,  food  and  the  maze  situation  become  associated.  Each 
rat,  after  the  initial  trials,  has  the  same  incentive.  But  the  human 
subject  has  no  such  incentive  and  no  criterion  of  success  unless 
he  is  told  what  he  is  to  do.  While  Webb’s  procedure  does  a  priori 
keep  the  conditions  for  human  and  animal  subjects  strikingly 
similar,  nevertheless,  the  action  of  the  subjects  indicates  that  the 
human  with  a  knowledge  of  the  problem  has  an  incentive  more 
nearly  comparable  to  that  of  the  rat  than  the  subject  without  such 
information.  A  comparison  of  the  records  for  a  group  of  ten  sub¬ 
jects  who  labored  through  the  maze  without  a  knowledge  of  what 
was  desired  of  them,  with  an  instructed  group  reveals  that  this 
information  is  effective  in  producing  a  drop  in  the  trial  score 
from  70.6  to  44.3;  in  the  total  error  score  from  476.1  to  325.1 ; 
and  in  the  total  time  score  from  2250.82"  to  1465.59".  Such  re¬ 
sults  refute  Webb’s10  assertion  that  knowledge  of  the  aim  in  the 
maze  problem  has  little  effect  on  learning. 

Because  of  the  great  difficulty  of  inducing  a  large  number  of 
rather  disinterested  subjects  to  serve  regularly  for  any  length  of 
time,  the  same  distribution  of  trials  was  not  employed  as  in  the 
case  of  the  investigation  with  animals.  The  experiment  was  so  ar¬ 
ranged  that  the  problem  could  usually  be  mastered  at  a  single  sit¬ 
ting.  No  subject  was  detained,  however,  for  more  than  1*4  hours 
at  a  time.  If  the  problem  was  not  mastered  within  this  period, 
the  subject  was  requested  to  return  every  48  hours  until  a  mastery 
was  effected.  If  a  subject  became  fatigued,  he  was  dismissed  after 
one  hour.  Between  the  first  and  second  trials,  as  well  as  between 
the  second  and  third,  a  rest  of  one  minute  was  granted.  If  the  first 
trial  required  more  than  fifteen  minutes,  the  subject  was  granted 
all  the  time  he  needed  to  recover  from  fatigue.  After  the  second 

10  Op.  cit.,  p.  15. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


9 


trial  a  rest  of  one  minute  was  given  between  groups  of  two  trials. 
This  distribution  of  effort  in  a  large  measure  obviated  fatigue, 
as  well  as  the  confusion  which  results  from  too  steady  application. 

The  subject  was  at  no  time  informed  that  he  was  being  guided. 
The  insertion  and  extraction  of  the  blocks  were  accomplished 
noiselessly. 

The  scheme  for  the  introduction  of  the  controlled  trials  was 
slightly  varied  from  the  one  employed  in  the  experimentation  up¬ 
on  the  animals,  in  order  to  bring  out  more  clearly  the  effect  upon 
learning  of  various  amounts  of  guidance.  Six  groups  of  subjects 
were  controlled  for  a  period  extending  over  two  successive  trials. 
The  control,  in  the  case  of  these  groups,  was  introduced  upon  the 
first,  third,  fifth,  seventh,  ninth  and  eleventh  trial,  respectively. 
Three  groups  of  subjects  were  each  granted  a  period  of  guidance, 
four  trials  in  length.  The  series  of  four  controlled  runs  began, 
respectively,  upon  the  first,  fifth  and  ninth  trial.  Two  groups 
were  guided  through  a  series  of  six  successive  trials,  one  of  the 
groups  being  guided  through  the  first  six  trials  of  the  learning 
period;  the  other,  from  the  seventh  to  twelfth  trial,  inclusive. 
Two  groups  of  subjects,  likewise,  were  given  eight  directed  trials; 
one  group  being  guided  from  the  first  to  the  eighth  trial,  inclusive ; 
the  other,  from  the  ninth  to  the  sixteenth.  One  group  was  guided 
through  the  initial  twelve  trials.  The  normal  group  learned  the 
maze  without  assistance. 

Each  of  the  fifteen  groups  consisted  of  ten  individuals — eight 
women  and  two  men.  All  were  students  or  instructors  at  the  Uni¬ 
versity  of  Chicago.  Most  of  the  subjects  were  naive,  so  far  as  the 
maze  situation  was  concerned.  The  few  students  who  were  famil¬ 
iar  with  the  maze  problem  were  equally  distributed  through  all  of 
the  groups,  in  order  to  prevent  a  weighting  of  the  results  by  this 
factor. 

The  retention  and  distraction  tests  were  carried  on  48  hours 
after  the  mastery  of  the  problem  had  been  effected.  Retention  was 
tested  by  a  single  tracing  of  the  maze. 

Each  subject  traced  the  maze  under  nine  different  distracting 
conditions.  The  distractions  employed  were  a  shifting  of  the  posi¬ 
tion  of  the  maze  through  90°,  180°  and  270°,  respectively;  the 


10 


HELEN  LOIS  KOCH 


silent  recitation  of  the  first  stanza  of  “Mary  had  a  little  lamb”; 
reading  aloud;  drawing  triangles  with  the  left  hand  while  the  right 
traversed  the  maze,  and  vice  versa;  tracing  the  maze  with  the 
left  hand;  and  traversing  it  from  the  so-called  goal  back  to  the  en¬ 
trance.  When  the  maze  was  shifted  90°  from  its  original  position, 
as  well  as  180°  and  270°,  the  subject  was  not  informed  of  the 
nature  of  the  change,  nor  was  he  told  that  he  was  being  distracted 
in  any  way.  This  procedure  of  keeping  the  subject  in  ignorance 
of  the  altered  environment  until  he  discovered  it  for  himself,  was 
adopted  in  order  that  the  conditions  might  more  closely  resemble 
those  of  general  life  in  which  changes  in  a  situation  are  seldom 
discreetly  labelled,  but  are  rather  left  to  the  individual  to  decipher. 


II 


THE  RELATIVE  EFFICACY  OF  CONTROL 
INTRODUCED  AT  VARIOUS  POSITIONS 
IN  THE  LEARNING  PROCESS 

It  is  of  great  practical  value  to  know  what  is  the  most  oppor¬ 
tune  time  in  the  learning  process  for  guiding  or  instructing  an  in¬ 
dividual  and  to  be  cognizant  of  the  effects  of  guidance  at  the 
various  stages  in  the  mastery  of  a  problem.  Toward  the  solution 
of  this  question  the  present  study  has  taken  only  one  small  step. 
Our  problem  is  a  description  and  analysis  of  the  relative  efficacy 
of  mechanical  guidance  introduced  at  various  stages  in  the  learn¬ 
ing  of  a  maze. 

For  purposes  of  analysis  it  is  desirable  to  consider  the  influ¬ 
ence  of  control  from  three  points  of  view :  namely,  from  the  point 
of  view  of  the  result  immediately  manifested,  the  result  subse¬ 
quently  exhibited,  and  the  total  result.  The  immediate  influence  of 
the  control  is  that  which  is  evident  during  the  period  in  which 
guidance  is  being  administered.  The  subsequent  influence  is  that 
manifested  in  the  undirected  trials  following  the  controlled  series. 
The  total  effect  is  a  composite  of  the  two  influences  just  described 
and  will  be  represented  by  such  measures  as  total  time,  total  errors 
and  total  trials. 

Before  a  discussion  of  the  results  is  attempted,  a  comment  on 
the  method  of  deriving  the  scores  is  necessary.  In  order  to  gain 
the  increased  validity  resulting  from  an  increase  in  the  number  of 
cases,  all  available  measures  which  bore  on  any  point  in  question 
were  employed.  There  were  ten  groups  of  rats,  for  example, 
which  were  unguided  in  the  first  two  trials.  Hence,  since  there 
were  ten  animals  in  each  group,  the  normal  score  for  these  two 
runs  is  an  average  of  one  hundred  measures.  The  scores  for  the 
eleventh  and  twelfth  trials  in  the  normal  series,  on  the  other 
hand,  are  based  upon  only  twenty  measures :  i.e.,  upon  the  records 
of  the  animals  in  the  group  which  received  no  guidance  and  those 


ii 


12 


HELEN  LOIS  KOCH 


in  the  group  guided  from  the  thirteenth  to  the  seventeenth  trial. 
The  other  eight  groups  whose  records  were  used  in  deriving  the 
scores  for  the  first  and  second  trials  had  received  some  guidance 
before  the  eleventh  run.  Since  a  normal  score  for  a  given  trial  is 
an  average  of  the  scores  for  an  unguided  run,  the  total  series  of 
trials  preceding  which  are  also  unguided,  the  records  of  these  eight 
groups  could  not  be  employed  in  computing  the  scores  for  the 
eleventh  and  twelfth  trials  in  the  normal  series. 

The  same  principles  of  selection  and  elimination  were  utilized 
in  deriving  the  scores  for  the  directed  trials.  There  were  five 
groups  which  were  guided  during  the  first  and  second  trials. 
Hence,  the  scores  for  the  first  two-  directed  runs  are  based  upon 
fifty  measures.  The  scores  for  the  third  and  fourth  trials,  when 
these  runs  are  themselves  controlled  and  preceded  by  directed 
trials  only,  are  computed  on  the  basis  of  forty  measures.  The 
record  of  that  group  receiving  guidance  in  only  two  of  the  initial 
trials  could  not  be  employed  in  computing  the  scores  for  these 
trials,  as  it  had  been  in  deriving  the  scores  of  the  first  two  directed 
runs.  Hence,  the  reason  for  the  reduction  from  fifty  to  forty 
measures  is  evident.  The  number  of  cases  used  in  deriving  any 
average  is  indicated  in  Table  i. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


13 


TABLE  1.  NUMBER  OF  CASES  USED  IN  COMPUTING 
A  GIVEN  SCORE— ANIMAL  SUBJECTS1 


Serial  Num¬ 
ber  of  the 
Trials  for 
which  an 
Average 
Score 
is  Sought 

Nature  of  the  Trials 

Number  of 
Uncontrolled 
Trials 
Preceding 
Trials  for 
which  an 
Average 
Score  is 
Sought 

Number  of 
Controlled 
Trials 
Preceding 
Trials  for 
which  an 
Average 
Score  is 
Sought 

Number  of 
Cases  upon 
which 
Average 
is  Based 

Controlled 

Uncontrolled 

1-2 

X 

100 

3-4 

X 

2 

80 

i-4 

X 

80 

5-6 

X 

4 

40 

1-6 

X 

40 

7-8 

X 

6 

30 

1-8 

X 

30 

9-10 

X 

8 

20 

I-IO 

X 

20 

11-12 

X 

10 

20 

1-12 

X 

20 

1-2 

X 

50 

3-4 

X 

2 

40 

i-4 

X 

40 

5-6 

X 

4 

30 

1-6 

X 

30 

7-8 

X 

6 

20 

1-8 

X 

20 

5-6 

X 

4 

20 

7-8 

X 

4 

2 

20 

5-8 

X 

4 

20 

5-8 

X 

4 

30 

5-12 

X 

4 

20 

3-io 

X 

2 

30 

4-9 

X 

3 

30 

7-12 

X 

6 

20 

9-12 

X 

8 

20 

1  All  scores  not  indicated  in  the  table  are  based  upon  10  cases. 


A.  Results  Based  upon  the  Records  of  Animal  Subjects 

1.  The  Influence  of  Two  Directed  Trials  Introduced  at  Various 

Positions  in  the  Learning  Process 

Let  it  be  recalled  that  there  were  three  groups  of  animals  which 
were  guided  for  only  two  trials.  One  of  these  groups  was  con¬ 
trolled  in  the  first  and  second  trials;  another,  in  the  sixth  and 
seventh  trials;  the  third  group,  in  the  eleventh  and  twelfth  trials. 
For  convenience,  the  groups  will  be  designated  by  the  numbers 


14 


HELEN  LOIS  KOCH 


2  (1-2),  2  (6-7),  2  (11-12),  respectively.  In  the  tables  and 
throughout  the  discussion  the  first  digit  in  the  configuration  will 
be  used  to  indicate  the  amount  of  guidance,  while  the  figures  in 
brackets  will  indicate  the  trials  in  which  guidance  was  given. 


TABLE  2.  INFLUENCE  OF  TWO  DIRECTED  TRIALS 
UPON  TRIALS— ANIMAL  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

25-5 

8-3 

24.67 

2  (6-7) 

28.8 

5-0 

14.70 

2  (n-12) 

3i-9 

1.9 

5-6o 

Influence  upon  trials :  It  is  apparent  from  Table  2  that  the  con¬ 
trol  in  the  three  positions  acts  to  reduce  the  number  of  trials  re¬ 
quired  for  learning  the  maze;  and  its  efficiency  is  greatest  when 
it  is  introduced  in  the  initial  trials.  This  beneficial  effect  decreases 
as  the  series  of  guided  runs  is  removed  farther  from  the  begin¬ 
ning. 

It  should  be  noted  that  the  probable  errors  are  not  given  in  the 
tables.  Because  of  the  ambiguity  of  the  meaning  of  this  measure 
when  based  upon  so  few  cases,  its  omission  was  deemed  advisable. 
The  reliability  of  the  results  may  be  judged  by  the  consistency  of 
the  general  tendencies  exhibited. 

The  symbol  of  negativity  employed  in  some  of  the  subsequent 
tables  also  requires  explanation.  It  is  used  when  the  score  of  the 
guided  group  is  greater  than  that  of  the  normal  group.  A  nega¬ 
tive  saving,  then,  of  an  absolute  or  relative  sort,  means  that  the 
score  of  the  controlled  group  exceeds  absolutely  or  relatively  that 
of  the  uncontrolled  group  by  the  amount  indicated. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


15 


TABLE  3.  INFLUENCE  OF  TWO  DIRECTED  TRIALS 
UPON  TOTAL  ERRORS— ANIMAL  SUBJECTS 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

143.22 

16.93 

10.57 

2  (6-7) 

120.16 

39-99 

24.97 

2  (11-12) 

14570 

14-45 

9.02 

Influence  upon  errors  (Table  3)  :  Guidance  reduces  the  total 
number  of  errors  made  in  the  entire  learning  process.  Group 
2  (6-7)  is  the  most  benefited;  groups  2  (1-2)  and  2  (11-12)  ex¬ 
hibit  about  the  same  amount  of  saving. 

By  a  detailed  examination  of  the  error  scores  we  may  ascertain 
some  of  the  factors  and  mechanisms  which  combined  to  produce 
the  totals  just  described.  The  immediate  effect  of  control  in  its 
most  obvious  form  is  the  prevention  of  cul-de-sac  errors.  The 
number  of  cul-de-sac  errors  prevented  during  the  control  period 
is  a  function  of  the  length  of  the  directed  series,  as  well  as  its 
position.  In  the  later  trials  when,  through  the  very  nature  of  the 
learning  process,  fewer  errors  are  being  made  than  early  in  the 
learning,  the  influence  of  the  guiding  device  as  a  means  of  pre¬ 
venting  errors  must  necessarily  decrease.  For  the  same  reason,  as 
the  series  in  any  given  position  increases  in  length,  the  saving  in 
cul-de-sac  errors  per  trial  decreases.  But  in  this  sheer  physical 
prevention  of  cul-de-sac  errors  we  have  little  interest.  The  truly 
significant  immediate  effect  of  the  control  will  be  revealed  in  the 
return  error  scores. 


i6 


HELEN  LOIS  KOCH 


TABLE  4.  IMMEDIATE  INFLUENCE  OF  TWO  DIRECTED 
TRIALS  UPON  ERRORS— ANIMAL  SUBJECTS 
A. 


Group 

Av.  No.  of  Cul-de- 
sac  Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

0 

6.06 

2  (6-7) 

0 

3-89 

2  (11-12) 

0 

3-05 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

22.11 

— 1. 00 

—474 

2  (6-7) 

•55 

2.41 

81.42 

2  (11-12) 

i-95 

—.92 

—89.32 

Table  4  indicates  that  the  control  has  little,  perhaps  even  a 
slightly  deleterious,  immediate  effect,  upon  the  return  errors  when 
it  is  introduced  in  the  initial  position.  This  unfavorable  influence 
on  return  errors  in  the  initial  trials  is,  doubtless,  a  result  of  the 
fact  that  in  the  early  stages  of  the  learning,  entrances  into  cul-de- 
sacs  do  operate  to  prevent  complete  returns  to  the  beginning  of  the 
maze.  When  the  cul-de-sacs  are  blocked,  the  animal  which  has 
once  headed  back  toward  the  starting  point  has  little  to  prevent 
a  complete  retracing  of  the  pathway.  Hence,  when  returns  are 
the  only  possible  errors,  more  of  them  are  made  than  when  cul- 
de-sacs  may  also  waylay  the  victim. 

Entrances  into  cul-de-sacs  in  the  intermediate  trials,  on  the 
other  hand,  instead  of  operating  to  prevent  complete  retracings, 
as  they  do  in  the  initial  trials,  tend  to  increase  the  opportunity  for 
retracing,  for  the  return  path  in  the  first  few  sections  of  the  maze, 
at  least,  has  by  the  sixth  trial,  as  a  rule,  been  well  mastered.  Hence, 
when  cul-de-sacs  are  blocked,  the  animal  that  is  still  in  a  some¬ 
what  exploratory  stage  of  the  learning  and  not  greatly  dependent 
on  fixed  cues,  is  guided  easily  forward  to  the  goal.  The  difficulties 
and  confusion  caused  by  the  cul-de-sacs  is  lacking.  Confusion  re¬ 
sulting  from  the  novelty  of  the  situation  has  worn  off.  This  com- 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


17 


plex  of  conditions  is  probably  the  explanation  of  the  large  abso¬ 
lute,  as  well  as  relative,  saving  in  return  errors  in  the  sixth  and 
seventh  trials. 

In  the  case  of  that  group  of  animals  for  whom  the  guided 
series  was  most  distantly  removed  from  the  beginning,  however,  a 
marked  increase  in  return  errors  is  exhibited  during  the  period 
of  control.  The  animal,  presumably,  by  the  eleventh  trial  has  be¬ 
come  greatly  dependent  on  certain  cues.  Blocking  the  entrances 
to  the  cul-de-sacs  modifies  some  of  the  cues,  causes  confusion, 
and,  since  return  errors  are  the  only  ones  possible,  more  of  them 
are  made  than  normally. 

In  our  tabular  analysis  of  the  subsequent  effect  of  control  we 
shall  consider  only  the  average  number  of  cul-de-sacs  and  the 
average  number  of  return  errors  amassed  per  trial  in  the  post¬ 
control  period.  For  a  more  minute  analysis  of  the  subsequent  in¬ 
fluence  of  guidance,  i.e.,  the  determination  of  the  period  of  great¬ 
est  influence,  the  persistence  of  the  effect,  the  conflict  of  the  dis¬ 
tracting  and  beneficial  forces,  we  may  rely  for  our  data  on  the 
learning  curves. 


TABLE  5.  SUBSEQUENT  EFFECT  OF  TWO  DIRECTED 
TRIALS  UPON  ERRORS— ANIMAL  SUBJECTS 
A. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
for  Trials  Subsequent 
to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

2.12 

—.14 

—7.07 

2  (6-7) 

•93 

.84 

4746 

2  (11-12) 

.92 

•37 

28.68 

B. 


1  i|  'I  - 

Group 

Av.  No.  of  Return 
Errors  per  Trial 
for  Trials  Subsequent 
to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

2.00 

—.88 

—85-98 

2  (6-7) 

.89 

— .08 

— 9-87 

2  (n-12) 

•65 

—.14 

—2745 

i8 


HELEN  LOIS  KOCH 


Group  2  (1-2)  manifests  an  increase  above  the  normal  in  the 
average  number  of  cul-de-sac  errors  amassed  per  trial  for  the 
period  subsequent  to  the  guided  interval;  groups  2  (6-7)  and 
2  (11-12)  exhibit,  on  the  other  hand,  a  positive  saving  (see  Table 
5).  Each  of  the  groups,  however,  was  unfavorably  influenced,  so 
far  as  the  average  number  of  return  errors  accumulated  per  trial 
in  the  post-control  period  is  concerned,  the  relative  loss  being 
greatest  for  group  2  (1-2),  least  for  group  2  (6-7).  It  is  signifi¬ 
cant  that  the  deleterious  influence  of  the  control  is  confined  largely 
to  the  realm  of  the  return  errors  and  that  in  each  group  the  return 
errors  fare  worse  than  the  cul-de-sacs.  Benefit,  then,  when  it  oc¬ 
curs,  is  in  terms  of  a  saving  in  those  errors  which,  during  the 
period  of  the  control,  had  been  prevented  by  physical  force. 

In  order  to  make  a  more  complete  analysis  of  the  influence  of 
control  upon  errors,  we  have  superimposed  the  curves  of  the  di¬ 
rected  groups  upon  that  of  the  normal  group.  The  discussion 
which  follows  is  based  upon  a  consideration  of  the  relations  be¬ 
tween  the  scores  of  the  normal  and  guided  groups  revealed  by  this 
device.  Immediately  following  the  period  of  control  the  curve  of 
group  2  (1-2) 2  exhibits  the  large  steeples  which  raise  it  alternately 
above  and  below  the  normal.  After  four  trials  characterized  by 
this  wavering,  the  curve  of  the  directed  group  follows  the  normal 
fairly  closely,  but  tends,  on  the  whole,  to  fall  slightly  more  rapidly 
and  irregularly.  The  steeples  following  the  period  of  control 
indicate  confusion.  It  is  significant  that  this  wavering  is  short¬ 
lived.  Reactions  developed  in  the  first  two  trials  have  little  oppor¬ 
tunity  to  become  fixed,  and,  hence,  the  period  of  their  effect  is 
limited. 

The  curve  for  the  group  guided  on  the  sixth  and  seventh  trials 
(Figure  2)  shows  somewhat  different  characteristics.  It  remains 
below  the  normal  curve  following  the  period  of  direction,  although 
exhibiting  many  steeples  and  a  tendency  to  a  slight  rise  in  the  eight 
trials  subsequent  to  the  control.  After  the  period  of  the  steeples, 
the  curve  follows  that  of  the  normal  group  with  little  significant 

2  Only  a  few  typical  curves  are  given.  The  reader  may  know  that  a  curve 
has  been  omitted  unless  it  is  referred  to  by  number  in  the  text. 


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Fig.  2.  A  limited  section  of  the  error  curve  of  groups  2  (6-7)  and  4  (1-4)  is 
shown  superimposed  upon  the  error  curve  of  the  unguided  group.  The  dashes 
denote  the  unguided  group ;  the  dots,  the  guided  trials  of  the  guided  groups ; 
the  solid  line,  the  unguided  trials  of  the  guided  groups. 


20 


HELEN  LOIS  KOCH 


'  deviation.  The  long  period  of  wavering  (extending  over  eight 
trials)  is  to  be  expected  because  the  reactions  to  the  maze  situation 
formed  in  the  trials  previous  to  the  period  of  guidance  have  be¬ 
come  fairly  clearly  defined,  though  not  rigidly  fixed.  The  steeples 
may  be  interpreted,  then,  to  represent  the  conflict  between  the 
somewhat  flexible  reactions  established  in  the  runs  preceding  the 
directed  trials  and  the  likewise  unstable  habits  formed  during  the 
short  period  of  control.  The  reactions  most  recently  made  seem, 
in  general,  to  triumph  over  those  most  frequently  made.  Hence, 
the  curve  of  the  guided  group  remains  below  the  normal. 

The  introduction  of  guidance  in  the  eleventh  and  twelfth  trials 
has  apparently  little  subsequent  effect  upon  the  errors,  for  the 
curve  of  the  guided  group  jumps  back  to  the  normal  after  the 
period  of  control  and  follows  the  normal  fairly  closely  thereafter. 
Pronounced  steeples  are  not  present.  The  situation  in  the  case  of 
group  2  (11-12)  probably  differs  from  that  of  group  2  (6-7)  in 
that  the  reactions  to  the  maze  have  become  well  fixed  by  the  elev¬ 
enth  trial.  Alteration  of  the  cues  during  the  eleventh  and  twelfth 
runs  causes  confusion;  but  the  change  in  the  situation  does  not 
continue  long  enough  to  uproot  habits  previously  well  established. 
Consequently,  when  the  control  is  removed,  the  animal  readily 
slips  back  to  his  former  modes  of  responding. 

The  important  facts  revealed  by  the  error  scores  are  as  fol¬ 
lows:  (1)  The  influence  of  the  control  is  selective.  When  errors 
are  reduced  in  the  runs  subsequent  to  the  guided  trials  they  are 
largely  those  which  were  prevented  during  the  period  of  guidance; 
namely,  the  cul-de-sac  errors.  Return  errors  tend  to  be  slightly 
increased  after  the  period  of  guidance.  (2)  Control  causes,  as  well 
as  prevents,  errors.  The  total  result  is  a  balance  of  the  two  ten¬ 
dencies.  (3)  Control  reduces  the  total  number  of  errors  made  dur¬ 
ing  the  whole  learning  process.  (4)  Interpolation  of  direction  in 
the  intermediate  position  results,  when  any  or  all  of  the  error 
scores  are  used  as  measures,  in  the  greatest  relative  gain  or  the 
least  relative  harm.  (5)  Although  the  number  of  errors  made  per 
trial  during  the  period  subsequent  to  control  may  be  increased, 
the  mastery  of  the  maze  may  still  be  attained  more  readily  than 
when  no  guidance  is  administered. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


21 


TABLE  6.  INFLUENCE  OF  TWO  DIRECTED  TRIALS 


A. 


UPON  TIME— ANIMAL  SUBJECTS 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

1389.86 

360.86 

20.61 

2  (6-7) 

I587-95 

162.77 

9-30 

2  (11-12) 

1754-43 

—3-71 

— 0.21 

B. 


Group 

Av.  Time 
per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

367.82 

142.69 

27-95 

2  (6-7) 

25.07 

23.02 

47.87 

2  (n-12) 

34.63 

—8.31 

—31.57 

C. 


Group 

Av.  Time  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

33.56 

— 11.72 

—53-66 

2  (6-7) 

20.78 

— .11 

—■53 

2  (n-12) 

21.24 

—3.21 

— 17.80 

Influence  upon  time  (Table  6)  :  The  influence  of  control  upon 
the  total  time  required  to  master  the  maze  is,  in  general,  beneficial. 
The  time  of  group  2  ( 1 1-12) ,  however,  differs  little  from  the  nor¬ 
mal.  The  efficacy  of  the  guidance  as  a  time-saving  device  varies  in¬ 
versely  as  the  distance  of  the  directed  series  from  the  initial  trial.3 

The  immediate  influence  of  guidance  upon  time  is  beneficial,  if 
the  period  of  control  is  not  too  far  removed  from  the  initial  trials. 
In  group  2  (11-12),  however,  an  increase  in  time  is  exhibited. 
Group  2  (6-7)  manifests  a  greater  relative  gain  than  group 
2  (1-2). 

Of  the  two  groups,  2  (1-2)  and  2  (11-12),  showing  a  large  in¬ 
crease  in  time  per  trial  in  the  runs  following  the  period  of  guid- 

3  The  time  scores  throughout  the  monograph  are  stated  in  seconds. 


22 


HELEN  LOIS  KOCH 


ance,  group  2  (1-2)  sustains  the  greatest  relative  loss.  This  dele¬ 
terious  subsequent  effect  of  control,  besides  being  a  result  of  dis¬ 
traction,  may  be  a  function  of  the  insufficient  opportunity  to  gain 
great  facility  in  running  the  true  pathway  of  the  maze,  which 
results  from  the  decrease  in  the  number  of  trials.  That  this  latter 
factor  is  not  alone  operative,  however,  is  evident  from  the  fact 
that  the  relative  loss  in  the  three  groups  does  not  vary  consistently 
with  the  number  of  trials  saved. 

Conclusion :  The  influence  of  control  upon  total  time,  errors 
and  trials  is  beneficial.  The  degree  of  benefit  in  trials  and  total 
time  is  inversely  proportional  to  the  distance  of  the  directed  series 
from  the  initial  trials.  The  intermediate  position  of  the  guided 
series  seems  most  favorable  to  the  reduction  of  errors.  The  imme¬ 
diate  effect  of  control  in  the  initial  position  and  in  the  position 
most  distantly  removed  from  the  early  trials  is  to  increase  the 
number  of  return  errors.  The  subsequent  effect  of  guidance  upon 
time  and  return  errors  is  deleterious. 

2.  Influence  of  Four  Directed  Trials  Introduced  at  Various 
Positions  in  the  Learning  Process 

Let  it  be  recalled  that  four  groups  of  animals  were  guided  for 
a  series  of  four  successive  trials.  Control  was  administered  from 
the  first  to  the  fourth,  from  the  fifth  to  the  eighth,  from  the  ninth 
to  the  twelfth,  and  from  the  thirteenth  to  the  sixteenth  trials  in  the 


various  groups. 

TABLE  7.  INFLUENCE  OF  FOUR  DIRECTED  TRIALS 
UPON  TRIALS— ANIMAL  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (i-4) 

22.0 

1 1.8 

34-9 

4  (5-8) 

28.1 

5-7 

16.9 

4  (9-12) 

29.1 

4-7 

139 

4  (13-16) 

28.8 

5-0 

14.8 

Influence  upon  trials  (Table  7)  :  The  positive  influence  of  these 
four-trial  series  upon  the  total  number  of  trials  necessary  to  master 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


23 


the  problem  manifests,  in  general,  as  in  the  two-trial  series,  a  de¬ 
creasing  magnitude  the  farther  the  position  of  the  series  is  from 
the  initial  trial.  The  most  marked  increase  in  the  number  of  trials 
— perhaps  the  only  significant  increase — resulting  from  position 
differences  in  the  controlled  series  appears  between  groups  4  (1-4) 
and  4  (5-8).  There  is  little  difference  in  the  amount  of  saving  in 
groups  4  (5-8),  4  (9-12)  and  4  (13-16) . 


TABLE  8.  INFLUENCE  OF  FOUR  DIRECTED  TRIALS 
UPON  TOTAL  ERRORS— ANIMAL  SUBJECTS 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (i-4) 

99.90 

60.25 

37.62 

4  (5-8) 

107.71 

52.44 

32.74 

4  (9-12) 

13303 

27.12 

16.93 

4  (13-16) 

144.65 

15-50 

9.68 

Influence  upon  errors :  As  in  the  case  of  trials,  the  control,  while 
always  resulting  in  a  saving,  decreases  in  efficiency  the  more  dis¬ 
tant  is  its  point  of  introduction  from  the  beginning  of  the  learning. 
The  total  error  score  (see  Table  8)  shows  a  regular  increase  from 
groups  4  (1-4)  to  4  (13-16). 

The  immediate  effect,  as  we  have  previously  indicated,  is  a 
function  of  the  sheer  physical  prevention  of  cul-de-sac  errors  and  a 
less  tangible  influence  upon  return  errors.  It  is  obvious  that  the 
number  of  cul-de-sac  errors  which  the  control  has  opportunity  to 
prevent,  decreases  in  accordance  with  the  nature  of  the  learning 
process  by  which  the  maze  is  mastered,  as  the  series  of  directed 
trials  is  removed  farther  from  the  beginning.  A  discussion  of  the 
influence  of  this  physical  factor  we  shall  omit  in  the  subsequent 
presentation  of  results. 

The  return  errors  amassed  per  trial  during  the  period  of  con¬ 
trol  (see  Table  9)  are  considerably  greater  in  number  in  three  of 
the  groups  than  those  made  in  the  corresponding  trials  of  the 
normal  group.  The  increase  above  the  normal  of  the  return  errors 
in  the  initial  trials  we  have  accounted  for  on  the  basis  of  a  ten¬ 
dency  to  complete  retracings  when  cul-de-sacs  are  not  present. 


24 


HELEN  LOIS  KOCH 


TABLE  9.  IMMEDIATE  EFFECT  OF  FOUR  DIRECTED  TRIALS 

UPON  ERRORS— ANIMAL  SUBJECTS 
A. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (i-4) 

0 

4.90 

4  (5-8) 

0 

3-8i 

4  (9-12) 

0 

3-47 

4  (13-16) 

0 

2-45 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (i-4) 

14-54 

—1-57 

— 12.10 

4  (5-8) 

2.89 

.11 

3-67 

4  (9-12) 

2.23 

— 1. 1 2 

— 10090 

4  (13-16) 

1-37 

—•47 

—52.22 

The  negative  saving  in  the  latter  trials,  it  is  reasonable  to  believe, 
results  from  the  conflict  of  habits  arising  from  the  alteration  in 
the  sensory  cues.  The  balance  of  factors  probably  contributing  to 
the  slight  positive  saving  in  the  return  errors  amassed  in  the  di¬ 
rected  trials  which  are  inserted  in  an  intermediate  position,  we 
have  described  in  the  discussion  upon  the  influence  of  two  con¬ 
trolled  trials. 

The  subsequent  effect  of  guidance  (see  Table  10),  so  far  as 
cul-de-sac  errors  are  concerned,  is  beneficial.  The  relative  positive 
effect  upon  cul-de-sac  errors  amassed  per  trial  increases  the  more 
distantly  removed  (within  certain  limits)  the  guided  series  is 
from  the  initial  trials.  This  effect  reaches  its  maximum  in  the  last 
few  of  the  first  twelve  trials  and  decreases  thereafter.  Guidance 
late  in  the  learning  can  do  little  but  interfere  with  a  well-nigh  per¬ 
fected  reaction  to  the  maze  situation. 

It  is  significant,  moreover,  that  in  each  of  the  groups  the  saving 
in  the  realm  of  cul-de-sac  errors  in  the  post-control  trials  is 
greater  than  in  the  realm  of  return  errors.  In  other  words,  those 
errors  which  were  previously  prevented  are  those  which  are  rela¬ 
tively  most  reduced  after  guidance  ceases. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


25 


TABLE  10.  SUBSEQUENT  EFFECT  OF  FOUR  DIRECTED  TRIALS 

UPON  ERRORS— ANIMAL  SUBJECTS 
A. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
for  the  Trials 
Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (i-4) 

1.46 

•85 

36.79 

4  (5-8) 

1 .01 

.60 

37.27 

4  (9-12) 

•75 

•54 

41.86 

4  (13-16) 

•7o 

.19 

21.35 

B. 


Group 

Av.  No.  of  Return 
Errors  per  Trial 
for  the  Trials 
Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(PerCent) 

4  (i-4) 

1.03 

—.29 

—39.18 

4  (5-8) 

•57 

.16 

21.92 

4  (9-12) 

•45 

.06 

IT. 76 

4  (U-16) 

•77 

-.38 

—97-44 

The  return  errors  made  per  trial  are  increased  above  the  nor¬ 
mal  in  the  post-control  period  when  the  guidance  is  administered 
in  the  initial  trials  or  late  in  the  learning  process.  The  negative 
saving  in  group  4(1-4)  is  probably  the  result,  to  a  large  extent, 
of  the  retracing  habit  set  up  in  the  initial  trials  and  accentuated  by 
confusion  resulting  from  changed  sensory  cues  upon  the  removal 
of  the  controlling  device.  In  group  4  (13-16),  however,  we  have 
reason  to  believe  that  this  apparently  great  increase  in  return  er¬ 
rors  is  a  function  of  the  distracting  effects  of  the  control,  for 
group  4  (9-12),  which  exhibits  a  greater  relative  loss  during  the 
period  of  direction,  nevertheless,  manifests  a  gain  in  the  post-con¬ 
trol  period.  The  length  of  the  guided  series,  we  may  argue,  was  not 
sufficient  to  permit  an  adjustment  to  the  cues  substituted  for  those 
fixed  through  twelve  trials  of  practice.  The  conflict,  then,  of  the 
partially  completed  readjustment  habits  with  the  old  habits  may 
have  been  the  cause  of  the  increase  in  errors.  Confusion  need  not 
have  been  very  pronounced,  however,  to  have  given  rise  to  the 


26 


HELEN  LOIS  KOCH 


apparently  enormous  relative  increase  in  return  errors,  since  a 
single  return  error  in  these  later  trials  has  great  weight. 

The  error  curves  of  the  four  groups  may  be  compared  on  the 
basis  of  regularity  and  speed  of  decline,  as  well  as  position  above  and 
below  the  normal.  Each  one  of  the  curves,  following  the  control 
period,  begins  below  the  normal.  The  post-control  period  is  char¬ 
acterized  by  steeples  which  lie  either  on  a  rising  or  level  curve,  thus 
indicating  a  time  of  great  uncertainty  on  the  part  of  the  rats. 
These  steeples  persist  for  six  trials  in  the  case  of  the  groups 
4  (5-8),  4  (9-12)  and  4  (13-16),  and  for  ten  trials  in  the  case 
of  the  group  guided  in  the  initial  runs  (Figure  2).  The  steeples 
are  not  sufficiently  high,  except  in  the  case  of  group  4  (13-16),  to 
cause  the  curve  of  the  controlled  group  to  cross  the  normal  for 
more  than  one  trial.  It  is  significant  that,  while  the  group  guided 
in  the  initial  trials  shows  the  greatest  disturbance,  a  readjustment 
is  readily  effected  and  the  curve  sinks  rapidly,  whereas,  when  con¬ 
trol  is  introduced  later  in  the  learning  process,  a  rapid  fall  is  not 
apparent. 

Influence  upon  time  (Table  11)  :  In  all  but  one  group,  guidance 
reduces  the  total  time  required  to  perfect  the  reaction  to  the  maze 
situation.  The  factors  influential  in  producing  these  totals  will  be 
revealed,  in  part,  by  an  inspection  of  the  time  scores  for  the  con¬ 
trol  and  post-control  periods,  as  well  as  the  scores  in  trials. 

The  immediate  effect  of  guidance  introduced  early  in  the  learn¬ 
ing,  when  habits  are  in  a  fluid  state,  is  a  reduction  in  the  time.  If 
control  is  introduced  later,  when  habits  have  crystallized,  a  marked 
loss  is  evidenced.  This  same  detrimental  influence  of  control  inter¬ 
polated  at  a  position  too  remote  from  the  initial  trials  was  mani¬ 
fested  in  the  error  scores.  Time  and  error  are,  of  course,  dependent 
variables.  Whether  or  not  time  increases  independently  of  errors 
matters  little,  for  an  increase  in  one  or  both  may  easily  be  ac¬ 
counted  for  in  terms  of  the  confusion  resulting  from  the  altera¬ 
tion  of  sensory  cues  which  had  been  well  integrated  into  the  habit¬ 
ual  reactions. 

With  the  exception  of  group  4  (5-8)  all  groups  manifest  in  the 
post-control  period  a  considerable  increase  above  the  normal  in 
the  average  time  consumed  per  trial.  This  increase,  however,  in 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


27 


TABLE  11.  INFLUENCE  OF  FOUR  DIRECTED  TRIALS  UPON 

TIME— ANIMAL  SUBJECTS 
A. 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (i-4) 

1298.97 

451-75 

25.80 

4  (5-8) 

1547.30 

203.42 

11.61 

4  (9-12) 

1841.39 

— 90.67 

—51.79 

4  (13-16) 

1722.91 

27.81 

1589 

B. 


Group 

Av.  Time 
per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (i-4) 

234-87 

76.59 

24.59 

4  (5-8) 

33.96 

13.87 

29.00 

4  (9-12) 

46.28 

—19.94 

—7570 

4  (13-16) 

31.66 

—11.63 

—58.06 

C. 


Group 

Av.  Time  per  Trial 
for  the  Trials 
Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (i-4) 

30.99 

— 9.62 

—45.01 

4  (5-8) 

i8.45 

•30 

1.60 

4  (9-12) 

25-37 

—7-34 

—40.71 

4  (13-16) 

19-59 

— 2.48 

—14.49 

time  per  trial  is  not  entirely  unambiguous  as  an  index  of  the  na¬ 
ture  of  the  influence  of  the  control.  All  of  the  groups  exhibit  a 
saving  in  trials.  Although  a  reduction  in  time  is  a  function  of  the 
accuracy  of  the  reaction  to  the  maze,  the  number  of  errors  made, 
it  is  also  a  function  of  the  speed  of  running  which  is  attained  as  a 
result  of  practice,  as  well  as  confidence  gained  with  experience. 
The  slight  saving  in  group  4  (5-8)  is  significant  because  it  oc¬ 
curs  in  spite  of  a  reduction  in  trials.  The  fact,  furthermore,  that 
the  increase  in  time  is  not  directly  proportional  to  the  reduction  in 
errors  indicates  that  control  does  have  an  influence  upon  time 
which  is  independent  of  trials. 


28 


HELEN  LOIS  KOCH 


The  time  curves  for  the  groups  guided  for  four  trials  reveal 
little  that  has  not  been  indicated  in  the  tables,  except  that  in  the 
final  stages  of  the  learning  the  time  scores  lie  below  the  normal; 
i.e.,  the  ultimate  effect  of  control  upon  time  is  beneficial.  Steeples 
indicating  uncertainty  are  unequivocally  present  in  the  case  of 
the  curves  for  groups  4  (1-4),  4  (9-12)  and  4  (13-16).  The 
steeples,  as  well  as  the  subsequent  descent  of  the  curve,  are  great¬ 
er  for  group  4  (1-4)  than  for  group  4  (9-12)  or  4  (13-16). 
This  indicates  greater  confusion,  but  more  rapid  readjustment 
when  control  is  introduced  in  the  initial  trials. 

Conclusion:  In  general,  the  saving  in  total  trials,  time  and  er¬ 
rors  is  positive  and  varies  inversely  as  the  distance  of  the  directed 
series  from  the  early  trials.  The  initial  position  is  decidedly  most 
favorable  to  the  reduction  of  trials.  The  saving  in  errors,  con¬ 
sidered  independent  of  trials,  is  largely  in  the  realm  of  cul-de-sac 
errors.  The  effect  of  control  upon  return  errors  is,  in  general, 
detrimental.  Especially  is  this  true  when  guidance  is  interpolated 
in  the  initial  trials  or  in  positions  well  removed  from  the  begin¬ 
ning. 

3.  Influence  of  Six  Directed  Trials  Introduced  at  Various 
Positions  in  the  Learning  Process 

The  series  of  six  successive  directed  trials  were  introduced 


upon  the  first,  fourth  and  seventh  run. 

TABLE  12.  INFLUENCE  OF  SIX  DIRECTED  TRIALS  UPON 

TRIALS— ANIMAL  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

6  (1-6) 

15.5 

18.3 

54-14 

6  (4-9) 

18.3 

15-5 

45-86 

6  (7-12) 

29.7 

4.1 

12.13 

Influence  upon  trials  (Table  12)  :  As  are  lesser  amounts  of 
guidance,  so  the  series  of  six  directed  trials  are  effective  in  reduc¬ 
ing  the  total  number  of  runs  required  to  master  the  problem.  The 
effectiveness  of  the  control,  as  an  agent  for  decreasing  the  total 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


29 


trials,  diminishes  as  its  point  of  interpolation  is  removed  more 
distantly  from  the  initial  runs. 


TABLE  13. 


A. 


INFLUENCE  OF  SIX  DIRECTED  TRIALS  UPON 
ERRORS— ANIMAL  SUBJECTS 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

6  (1-6) 

6973 

90.42 

56.46 

6  (4-9) 

73-55 

86.60 

54.07 

6  (7-12) 

1 16. 16 

43-99 

27.47 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

6  (1-6) 

10.87 

—2.05 

—23.24 

6  (4-9) 

•37 

1.96 

84.12 

6  (7-12) 

1.38 

•32 

18.82 

C. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

6  (1-6) 

•43 

1.32 

75-43 

6  (4-9) 

•54 

•95 

63.76 

6  (7-12) 

.70 

•59 

4573 

D. 


Group 

Av.  No.  of  Return 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

6  (1-6) 

.60 

.28 

31.82 

6  (4-9) 

.51 

.14 

21.54 

6  (7-12) 

•45 

.06 

11.76 

Influence  upon  errors  (Table  13)  :  A  similar  tendency  for  the 
effectiveness  of  the  control  to  decrease,  the  later  it  is  given  in  the 


30 


HELEN  LOIS  KOCH 


learning  process,  is  evident  in  the  total  error  scores.  The  initial 
and  intermediate  positions,  however,  differ  relatively  little  in  ef¬ 
fectiveness. 

The  immediate  result  of  the  control,  measured  in  terms  of  re¬ 
turn  errors,  manifests,  likewise,  the  same  tendencies  that  we  have 
noted  in  our  consideration  of  the  influence  of  various  other 
amounts  of  guidance.  The  number  of  return  errors  accumulated 
during  the  directed  series  in  the  initial  position  is  greater  than 
that  amassed  by  the  normal  group.  The  usual  negative  saving  in 
the  directed  trials  interpolated  in  the  final  position  is  not  present, 
though  in  comparison  with  group  6  (4-9),  a  decided  decrease  in 
relative  saving  is  shown.  Since  the  point  of  the  introduction  of 
the  control,  as  the  series  grows  longer,  occurs  earlier  in  the  learn¬ 
ing  process — when  habits  have  not  become  well  fixed — it  is  rea¬ 
sonable  to  expect  that  the  most  distracting  effect  would  not  be  so 
prominent,  and  hence,  a  saving  in  return  errors  more  probable, 
than  in  the  case  of  the  shorter  series. 

The  subsequent  influence  of  the  control  upon  the  errors,  both 
return  and  cul-de-sac,  made  per  trial  is  beneficial ;  but  the  relative 
saving  decreases  the  farther  the  position  of  the  directed  series  is 
from  the  initial  trial.  Again,  it  is  worthy  of  note  that  the  saving 
in  cul-de-sac  errors  is  much  greater  in  each  group  than  the  rela¬ 
tive  saving  in  return  errors. 

The  error  curves  reveal  little  that  is  new.  The  curve  for  group 
6  (1-6)  begins,  subsequent  to  the  period  of  direction,  below  the 
normal  curve.  It  exhibits  only  one  steeple  and  then  falls  rapidly 
and  regularly  to  the  base  line.  In  no  place  does  it  rise  above  the 
normal  curve.  The  curve  for  group  6  (4-9)  (Figure  3)  rises 
in  the  trials  immediately  succeeding  the  period  of  guidance,  but 
crosses  the  normal  curve  only  once.  It  has  three  pronounced 
steeples  before  beginning  its  decline,  which,  when  once  started,  is 
rapid  and  fairly  regular.  The  curve  for  group  6  (7-12),  on  the 
other  hand,  does  not  manifest  very  marked  steeples.  While  it  does 
start  below  the  normal  in  the  post-control  period  it  quickly  rises 
to  meet  the  normal  and  follows  the  latter  closely.  The  persistence 
of  the  effect  of  the  guided  series,  when  it  is  introduced  late  in  the 
learning  process,  as  well  as  the  magnitude  of  the  effect,  is  slight. 


ss 


3o 


» 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 


Fig.  3.  A  limited  section  of  the  error  curve  of  groups  6  (4-9)  and  12  (1-12) 
is  shown  superimposed  upon  the  error  curve  of  the  unguided  group.  The 
dashes  denote  the  unguided  group ;  the  dots,  the  guided  trials  of  the  guided 
groups;  the  solid  line,  the  unguided  trials  of  the  guided  groups. 


32 


HELEN  LOIS  KOCH 


The  curves,  then,  reveal  that  ( i )  the  most  persistent  effect  is  ap¬ 
parent  when  the  earlier  trials  are  guided;  (2)  the  wavering  pro¬ 
duced  by  the  abstraction  of  the  control  is  greatest  in  the  interme¬ 
diate  period;  and  (3)  that  the  least  effect  is  exhibited  under  the 
condition  in  which  control  occurs  late  in  the  learning. 


A. 


TABLE  14.  INFLUENCE  OF  SIX  DIRECTED  TRIALS  UPON 

TIME— ANIMAL  SUBJECTS 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

6  (1-6) 

1079.61 

671. 11 

38.33 

6  (4-9) 

1238.94 

511.78 

29.23 

6  (7-12) 

1628.95 

121.77 

6.96 

B. 


Group 

Av.  Time 
per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

6  (1-6) 

174-59 

2.10 

1. 19 

6  (4-9) 

20.58 

14.41 

41.19 

6  (7-12) 

25-77 

4.18 

13-95 

C. 


Group 

Av.  Time  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

6  (1-6) 

18.24 

1.78 

8.89 

6  (4-9) 

I4-I5 

4-95 

25.92 

6  (7-12) 

18.26 

—•23 

— 1.28 

Effect  upon  time  (Table  14)  :  The  total  time  necessary  for  mas¬ 
tering  the  problem  varies  directly  with  the  distance  from  the  ini¬ 
tial  trial  at  which  guidance  is  given.  Control  in  all  cases,  however, 
reduces  the  time. 

The  immediate  effect  of  the  control  upon  time  presents  a  slight¬ 
ly  different  picture.  When  guidance  occurs  in  the  initial  position, 
its  apparent  influence  is  almost  negligible;  but  when  it  occurs  in 
the  intermediate  and  final  positions,  a  large  relative  saving  is  ex- 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


33 


hibited.  The  marked  reduction  in  time  per  trial  for  those  trials  in 
the  intermediate  position  is  probably  mediated  largely  by  the  re¬ 
duction  in  errors  which  we  have  already  described. 

Of  the  balance  of  factors  tending  to  increase  the  time  per  run 
in  the  post-control  period  and  those  tending  to  facilitate  the  run¬ 
ning,  the  latter  are  dominant  in  groups  6  (1-6)  and  6  (4-9),  but 
most  influential  in  the  case  of  group  6  (4-9).  The  slight  increase 
in  time  per  trial  for  the  trials  following  the  directed  series  in  group 
6(7-12)  is  significant,  since  it  is  the  only  hint  we  have  of  the  usual 
confusion  attendant  upon  the  late  introduction  of  the  control. 
The  distracting  phase  of  the  control’s  influence  was  not  manifested 
in  the  error  scores  as  it  usually  is. 

The  time  curves  add  little  to  the  information  furnished  by 
the  tables,  except  in  regard  to  the  persistence  of  the  influence  of 
the  control.  The  time  curve  for  group  6  (1-6)  starts,  in  the  period 
subsequent  to  the  control,  below  the  normal  and,  like  the  error 
curve  for  the  same  group,  has  one  marked  steeple  before  its  regu¬ 
lar  descent  begins.  The  curve  for  group  6  (4-9)  remains  always 
below  the  normal;  but  a  series  of  small  steeples  indicate  that  con¬ 
fusion  was  operative  over  a  longer  period  than  in  the  previous 
group.  The  curve  for  group  6  (7-12),  on  the  other  hand,  crosses 
and  lies  above  the  normal  curve  for  some  time.  Its  descent  is  slow, 
but  slightly  more  regular  than  that  of  the  normal  curve. 

Conclusion:  The  efficacy  of  the  control,  measured  in  terms  of 
total  trials,  total  errors  and  total  time,  varies  inversely  with  the 
distance  of  the  guided  series  from  the  initial  run.  Guidance  given 
in  the  intermediate  position  is  favorable  in  its  immediate  effect 
upon  both  time  and  errors ;  and  the  relative  degree  of  its  influence 
is  greater  than  that  of  control  occurring  earlier  or  later.  The  sub¬ 
sequent  effect  of  the  control  upon  errors  is  favorable.  It  is  greater 
in  the  realm  of  the  cul-de-sac  than  return  errors,  and  varies  for 
both  types  inversely  as  the  distance  of  the  directed  trials  from  the 
beginning  of  the  learning  process. 


34 


HELEN  LOIS  KOCH 


4.  Influence  of  Eight  Directed  Trials  Introduced  at  Various 
Positions  in  the  Learning  Process 

Three  positions  of  a  series  of  eight  successive  trials  were  em¬ 
ployed.  The  guided  series  began  upon  the  first  trial,  the  third  trial 
and  the  fifth  trial. 

TABLE  15.  INFLUENCE  OF  EIGHT  DIRECTED  TRIALS  UPON 

TRIALS— ANIMAL  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(PerCent) 

8  (1-8) 

19.9 

13-9 

41.12 

8  (3-10) 

30.6 

3-2 

946 

B  (5-12) 

26.8 

7.0 

20.71 

Influence  upon  trials  (Table  15)  :  All  groups  exhibit  a  positive 
saving  in  trials;  but  in  this  series  we  meet  the  first  exception  to 
the  rule  that  the  efficacy  of  the  control,  as  measured  in  terms  of  the 
number  of  trials  required  for  learning  the  problem,  varies  inverse¬ 
ly  as  the  distance  of  the  directed  series  from  the  initial  trials. 
Group  8  (5-12)  exhibits  a  greater  saving  in  trials  than  does  group 
8  (3-10).  For  this  no  explanation  is  apparent  except  that  of  the 
chance  assembling  in  one  group  of  several  animals  which  behaved 
eccentrically.  One  animal,  for  instance,  after  he  had  practically 
mastered  the  problem,  consumed  twenty-six  trials  in  the  elimina¬ 
tion  of  one  error. 

Influence  \ upon  errors  (Table  16)  :  Guidance  effects  a  marked 
positive  saving  in  the  total  number  of  errors  made  by  each  of  the 
three  groups.  The  initial  position  seems  most  efficient  for  error 
reduction.  The  intermediate  and  final  positions  of  the  control 
seem  about  equally  effective. 

The  immediate  influence  of  guidance  administered  for  eight 
trials  shows  some  tendencies  not  hitherto  displayed.  The  positive 
saving  in  return  errors  made  during  the  period  of  control  which 
includes  the  initial  trials  is  contrary  to  our  usual  findings.  That 
it  is  no  chance  result  is  supported  by  the  fact  that  the  average 
number  of  return  errors  made  in  the  first  twelve  trials  by  the 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


35 


TABLE  1 6. 
A. 


INFLUENCE  OF  EIGHT  DIRECTED  TRIALS  UPON 
ERRORS— ANIMAL  SUBJECTS 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

8  (1-8) 

71.53 

88.62 

55-34 

8  (3-10) 

108.63 

51-52 

32.17 

8  (5-12) 

107.71 

52.44 

32.74 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

8  (1-8) 

5.84 

1.08 

1567 

8  (3-10) 

1. 61 

•59 

26.82 

8  (5-12) 

2. 43 

“•23 

—10.45 

C. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

8  (1-8) 

•45 

1. 16 

72.05 

8  (3-10) 

•93 

.46 

33.09 

8  (5-12) 

.70 

•59 

45-73 

D. 


Group 

Av.  No.  of  Return 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

8  (1-8) 

•30 

•43 

58.90 

8  (3-10) 

•95 

—•35 

—58.33 

8  (5-12) 

•50 

.01 

1.99 

group  guided  during  these  runs  also  exhibits  a  saving  (of  29%) 
over  the  normal.  The  hypothesis  previously  advanced  that  cul-de- 
sacs  do  prevent  complete  retracings  and  hence  their  absence  in¬ 
creases  the  return  error  score  applies,  then,  only  to  the  first  six 
trials.  The  groups  guided  for  more  than  six  of  the  initial  trials 


36 


HELEN  LOIS  KOCH 


have  practically  mastered  the  true  pathway  of  the  maze.  The  re¬ 
tracing  habit  is  readily  eliminated  in  a  cul-de-sac-less  maze,  as 
soon  as  the  association  between  food  and  the  maze  situation  has 
been  well  established. 

The  negative  saving  in  the  number  of  return  errors  made  dur¬ 
ing  the  period  of  control  by  the  group  whose  guided  trials  were 
most  distantly  removed  from  the  initial  run  is  in  accord  with  a 
tendency  which  we  have  previously  noted  and  accounted  for  on  the 
basis  of  confusion  resulting  from  the  altered  sensory  cues. 

The  large  positive  saving  in  return  errors  in  group  8  (3-10)  is, 
probably,  due  to  the  fact  that  guidance  was  introduced  sufficiently 
early  to  avoid  conflict  with  any  fixed  maze  habits  and  to  prevent 
the  formation  of  any  elaborate  retracing  habits  resulting  from  the 
absence  of  cul-de-sacs. 

In  all  of  the  records  used  to  analyze  the  effect  of  control  upon 
the  behavior  in  the  post-control  period,  the  three  groups  we  are 
discussing  maintain  the  same  relative  rank.  Group  8  (1-8)  ranks 
first;  group  8  (5-12),  second;  and  group  8  (3-10),  third.  The 
saving  in  cul-de-sac  errors  is  greater  than  in  the  realm  of  return 
errors  in  each  of  the  groups.  It  is  significant,  also,  that  initial 
guidance,  as  in  the  case  of  the  six-trial  series,  is  the  most  bene¬ 
ficial  in  its  subsequent  influence.  Probably  two  alterations  of  sen¬ 
sory  cues  (the  introduction  and  removal  of  the  control),  if  the 
guided  series  is  sufficiently  long  to  permit  the  development  of  a 
genuine  dependence  upon  the  cues,  are  more  disturbing  than  one 
alteration;  namely  the  mere  removal  of  the  control. 

The  rather  high  cul-de-sac  error  score  of  group  8  (3-10)  for 
the  post-control  period  is  somewhat  difficult  to  account  for,  except 
in  terms  of  chance.  The  fact  that  the  group  which  did  excel  during 
the  period  of  guidance  suffers  this  increase  in  return  errors  in  the 
trials  following  the  period  of  guidance,  gives  plausibility  to  the 
explanation  couched  in  terms  of  chance.  It  is  possible,  of  course, 
that  change  of  cues  upon  the  eleventh  trial  is  particularly  disrupt¬ 
ing.  This  assumption  of  the  unique  nature  of  the  eleventh  trial 
seems,  however,  fanciful  to  the  writer. 

The  curves  of  all  the  groups  show  a  marked  wavering  in  the 
post-control  period.  The  curve  of  group  8  (1-8),  which  through- 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


37 


out  all  its  course  remains  below  the  normal,  exhibits  small  steeples 
for  eleven  trials  immediately  after  guidance,  then  drops  suddenly 
and  regularly  to  the  base  line.  The  curve  for  group  8  (3-10)  starts 
below  the  normal  curve  in  the  post-control  period ;  but  its  steeples, 
which  persist  for  about  eleven  trials,  rise  alternately  above  and 
below  the  normal.  Subsequent  to  this  period  of  rather  conspicuous 
wavering,  the  curve  follows  the  general  course  of  the  normal 
curve.  The  curve  for  group  8  (5-12)  exhibits  a  period  of  waver¬ 
ing  covering  seven  trials,  in  which  the  steeples  rise  alternately 
above  and  below  the  normal.  In  the  latter  part  of  its  course  the 
curve  sinks  below  the  normal  and  remains  consistently  slightly 
below.  While  the  period  of  wavering  has  about  the  same  extent  in 
all  of  the  groups,  the  readjustment,  as  we  have  frequently  indi- 


TABLE  1 7.  INFLUENCE  OF  EIGHT  DIRECTED  TRIALS  UPON 

TIME— ANIMAL  SUBJECTS 
A. 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

8  (1-8) 

1076.73 

673.99 

38.50 

8  (3-10) 

1537.65 

213.07 

12.17 

8  (5-12) 

1476.37 

274-35 

15.67 

B. 


Group 

Av.  Time 
per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

8  (1-8) 

88.60 

i6.57 

1576 

8  (3-10) 

27.67 

10.16 

26.86 

8  (5-12) 

25.85 

6.46 

19.99 

C. 


Group 

Av.  Time  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

8  (1-8) 

1372 

5-03 

26.83 

8  (3-10) 

19.20 

—•25 

—1.32 

8  (5-12) 

14.32 

371 

20.58 

38 


HELEN  LOIS  KOCH 


cated,  is  more  rapid  and  regular  when  guidance  is  administered 
in  the  initial  trials. 

Influence  upon  time  (Table  17)  :  The  records  and  curves  re¬ 
veal  few  tendencies  which  could  not  have  been  predicted  from  the 
error  records  and  accounted  for  on  the  basis  of  the  same  factors 
operative  in  making  the  error  records  as  they  are.  A  detailed 
discussion  of  the  results  would  accomplish  little. 

Conclusion :  Eight  directed  trials  introduced  in  the  initial  po¬ 
sition  are  most  effective  in  reducing  trials,  errors  and  time ;  eight 
controlled  trials  in  the  intermediate  position  are  least  effective, 
though  still  beneficial. 

B.  Results  Based  upon  the  Records  of  Human  Subjects 

Our  general  method  of  deriving  scores  we  have  already  dis¬ 
cussed  at  the  beginning  of  the  chapter.  Table  18  merely  furnishes 
the  data  with  respect  to  the  number  of  cases  used  in  computing 
the  scores  based  upon  the  records  of  the  human  subjects. 

1.  Influence  of  Two  Directed  Trials  Introduced  at  Various 
Positions  in  the  Learning  Process 

In  the  experiment  conducted  upon  human  subjects,  six  groups 
were  guided  for  two  successive  trials.  The  introduction  of  the 
directed  series  occurred  in  the  various  groups  upon  the  first,  third, 
fifth,  seventh,  ninth  and  eleventh  trial,  respectively.  The  groups  so 
guided  will  be  referred  to  as  H2  (1-2),  H2  (3-4),  H2  (5-6), 
H2  (7-8),  H2  (9-10)  and  H2  (11-12). 

Influence  upon  trials  (Table  19)  :  With  one  exception,  two  di¬ 
rected  trials,  whatever  their  position,  have  a  beneficial  effect, 
when  this  effect  is  measured  in  terms  of  the  number  of  trials  re¬ 
quired  to  master  the  problem.  Guidance  in  the  initial  trials  acts  to 
reduce  the  number  of  runs.  Control  in  the  third  and  fourth  trials, 
on  the  other  hand,  effects  a  marked  increase  above  the  normal  in 
the  number  of  runs  required;  but  after  the  fourth  trial,  guidance 
again  results  in  a  saving  which  increases  as  the  series  is  interpo¬ 
lated  farther  and  farther  from  the  beginning.  There  is,  however, 
an  optimum  position  (ninth  and  tenth  trials)  beyond  which  the 
efficacy  of  the  control  appears  to  decrease.  This  is  at  variance 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


39 


TABLE  1 8.  NUMBER  OF  CASES  USED  IN  COMPUTING  A 
GIVEN  SCORE— HUMAN  SUBJECTS  4 


Serial  Num¬ 
ber  of  the 
Trials 

for  which  an 
Average 
is  Sought 

Nature 

Tn 

Con¬ 

trolled 

of  the 
lals 

Uncon¬ 

trolled 

No.  of  Uncon¬ 
trolled  Trials 
Preceding 
Trials  for  which 
an  Average 
Score  is  Sought 

No.  of  Con¬ 
trolled  Trials 
Preceding 
Trials  for  which 
an  Average 
Score  is  Sought 

No.  of 
Cases 

upon  which 
Average 
is 

Based 

1-2 

X 

100 

3-4 

X 

2 

90 

i-4 

X 

90 

5-6 

X 

4 

70 

1-6 

X 

7o 

7-8 

X 

4 

50 

1-8 

X 

50 

5-6 

X 

4 

20 

5-8 

X 

4 

50 

7-8 

X 

6 

20 

9-10 

X 

.  8 

30 

1-2 

X 

50 

3-4 

X 

2 

40 

i-4 

X 

40 

5-6 

X 

4 

30 

1-6 

X 

30 

7-8 

X 

6 

20 

1-8 

X 

20 

11-12 

X 

8 

2 

20 

9-12 

X 

8 

20 

4  All  scores  not  indicated  in  the  table  are  based  upon  io  cases. 


TABLE  19.  INFLUENCE  OF  TWO  DIRECTED  TRIALS 
UPON  TRIALS— HUMAN  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

36.9 

74 

16.70 

H2  (3-4) 

50.4 

— 6.1 

— 13-77 

H2  (5-6) 

43-0 

1-3 

2-93 

H2  (7-8) 

41. 1 

3-2 

7.22 

H2  (9-10) 

35-6 

8.7 

19.64 

H2  (11-12) 

38.3 

6.0 

13.54 

with  most  of  our  findings  in  regard  to  the  performance  of  the 
animals.  Since  human  subjects  differ  from  animals,  at  least  in  the 
amount  of  their  ideational  content,  our  explanations  of  this  dif¬ 
ference  in  results  need  not,  then,  be  couched  wholly  in  gross  senso- 
ri-motor  terms.  Guidance  in  the  initial  trials  prevents  the  forma¬ 
tion  of  some  bad  habits  and  enters  little  into  conflict  with  habits 


40 


HELEN  LOIS  KOCH 


already  set  up.  In  the  later  trials,  when  the  maze  habit  is  fairly 
well  fixed,  the  control,  while  perhaps  causing  some  confusion, 
does  call  the  attention  of  the  alert  and  analyzing  human  subject  to 
certain  of  the  critical  elements  of  the  situation.  The  location  of 
the  troublesome  elements  in  the  problem  aids  in  a  rapid  adjust¬ 
ment.  In  the  trials  succeeding  the  first  few,  on  the  other  hand, 
when  the  reaction  is,  at  best,  in  a  fluid  state  and  cues  have  little 
meaning,  changes  in  the  situation  tend  to  disrupt  the  proper  habits 
that  are  in  the  process  of  fixation.  Temporary  hypotheses  in  re¬ 
gard  to  the  correct  path  are  demonstrated  invalid,  not  because  they 
were  not  in  the  first  place  proper,  but  because  of  the  changing  con¬ 
ditions  of  which  the  subject  is  not  informed. 

Whether  the  slight  decline  in  the  saving  exhibited  by  group 
H2  (11-12)  as  contrasted  with  H2  (9-10)  is  a  chance  occurrence 
or  a  tendency  that  would  clearly  define  itself  were  guidance  inter¬ 
polated  at  a  number  of  positions  subsequent  to  the  twelfth  trial, 
we  can  not  say.  A  decrease  in  effectiveness,  however,  one  would 
be  justified  in  expecting.  By  the  tenth  trial,  habits  have,  pre¬ 
sumably,  become  so  well  ingrained  that  much  of  their  plasticity 
has  been  lost.  Guidance,  at  this  stage  or  later,  is  more  likely  to  be 
confusing,  in  certain  of  its  aspects,  than  if  it  were  introduced 
slightly  earlier,  although  its  total  effect  may  still  be  favorable. 

Influence  upon  errors  (Table  20)  :  The  total  error  scores  show 
a  tendency  similar  to  that  manifested  in  the  trials.  Initial  guidance 
and  the  directed  series  located  latest  in  the  trial  sequence  are  bene¬ 
ficial  in  their  effects ;  control  in  the  intermediate  position  is  detri¬ 
mental,  or  only  slightly  favorable.  The  large  saving  in  group 
H2  (1-2)  is  significant.  It  supports  the  doctrine  that  it  is  better 
to  avert  bad  habits  than  to  disrupt  them  mechanically  or  call  atten¬ 
tion  to  them  later  in  the  learning. 

The  tendencies  apparent  in  the  scores  indicating  the  immediate 
influences  of  the  control  are  somewhat  different  from  those  evi¬ 
denced  in  the  scores  made  by  the  animals.  The  large  saving  in  the 
return  errors  when  guidance  occurs  early  in  the  learning  is  one 
noteworthy  deviation  from  the  results  obtained  in  the  experiment 
upon  rats.  The  stylus  maze  has,  probably,  difficulties  for  man  that 
the  large  maze  does  not  present  to  the  animal.  The  turns  in  the 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


4i 


So 

85 
SO 
75 

7* 
65 

GO 

55 

SO 

75 

70  i 

i 

i 

35  \ 


3o 


Group 


Y/-2.J 


I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

:i 

:i 

:l 

:l 

:l 

:l 

:i 

:• 

:» 

:l 

:i 

•i 

•I 

•i 

:l 

:1 

a 

:» 

:l 
:l 
•  I 
:  I 
:  I 

•I 

:  I 
: » 

:  i 

:  I 

:  • 
:  i 
» 


Group 


H12 


Fig.  4.  A  limited  section  of  the  error  curve  of  groups  H2  (1-2)  and 
H 12  (1-12)  is  shown  superimposed  upon  the  error  curve  of  the  unguided  group. 
The  dashes  denote  the  unguided  group ;  the  dots,  the  guided  trials  of  the 
guided  groups ;  the  solid  line,  the  unguided  trials  of  the  guided  groups. 


42 


HELEN  LOIS  KOCH 


A. 


TABLE  20.  INFLUENCE  OF  TWO  DIRECTED  TRIALS 
UPON  ERRORS— HUMAN  SUBJECTS 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

289.5 

104.2 

26.47 

H2  (3-4) 

410.2 

—16.5 

—4.19 

H2  (5-6) 

427.6 

—33-9 

—8.61 

H2  (7-8) 

378.3 

154 

3-9i 

H2  (9-10) 

367.8 

25.9 

6.58 

H2  (11-12) 

355-5 

38.2 

9.70 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

39-15 

17.20 

30.53 

H2  (3-4) 

H-55 

13.65 

54.18 

H2  (5-6) 

9.68 

1.94 

16.84 

H2  (7-8) 

8.72 

—1.94 

— 28.61 

H2  (9-10) 

9-57 

—5.82 

—155-20 

H2  (n-12) 

3.80 

•35 

8.43 

C. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

2.19 

-.46 

—26.59 

H2  (3-4) 

1.50 

.04 

2.60 

H2  (5-6) 

1.67 

—•36 

—27.48 

H2  (7-8) 

1.29 

— .08 

—6.61 

H2  (9-10) 

1.36 

—.18 

—15.25 

H2  ( 1 1-12) 

1. 16 

—.18 

—18.37 

D. 


Group 

Av.No.of  Return 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

3-39 

—•51 

— 17.71 

H2  (3-4) 

3-28 

—.88 

—36.67 

H2  (5-6) 

2.74 

-.89 

— 48. 1 1 

H2  (7-8) 

2.06 

-.46 

—28.75 

H2  (9-10) 

i-75 

—.41 

—30.59 

H2  (11-12) 

1.52 

—.18 

—1343 

THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


43 


true  pathway  offer  little  obstruction  to  the  rat;  but  to  the  human 
subject  who  is  deprived  of  his  faithful  servant,  vision,  and  is  little 
at  ease  when  relying  entirely  on  contact  or  kinaesthesis  for  guid¬ 
ance,  the  small  corners  and  turns  of  the  true  pathway,  for  no  very 
small  number  of  the  early  trials,  act  as  effectively  as  obstructions 
to  his  progress  as  do  the  blind  alleys.  For  minutes  at  a  time  he 
will  work  the  stylus  back  and  forth  in  a  path  that  should  offer  him 
no  resistance.  Hence,  the  tendency  to  complete  retracings  in  the 
cul-de-sac-less  maze  is  not  exhibited  in  the  early  trials,  as  it  is  in 
the  case  of  the  rats.  Since,  therefore,  returns  are  not  likely  to  be 
encouraged  by  the  absence  of  cul-de-sacs,  and  no  fixed  habits  are 
interfered  with  by  the  control,  the  marked  relative  saving  in  the 
initial  trials  is  to  be  expected. 

The  distracting  phase  of  the  control’s  influence,  as  in  the  ex¬ 
periment  upon  animals,  is  on  the  ascendency,  relatively  at  least, 
in  the  later  trials.  It  is  reasonable  to  suppose  that  the  later  the 
interpolation  of  the  guidance  occurs,  and  the  more  fixed  the  habits 
with  which  it  enters  into  conflict,  the  more  disturbing  it  will  be. 
The  positive  saving  in  return  errors  exhibited  by  group  H2  ( 1 1-12 ) , 
which  is  an  exception  to  the  principle  just  enunciated,  has  the  ear¬ 
marks  of  a  chance  result.  The  fact  that  the  normal  score  for  the 
eleventh  and  twelfth  trials  is  higher  than  that  for  the  ninth  and 
tenth  is  scarcely  in  accord  with  what  we  know  of  the  learning  pro¬ 
cess.  Were  the  normal  score  for  the  eleventh  and  twelfth  trials 
lower,  or  even  the  same  as  that  for  the  ninth  and  tenth  runs,  an 
increase  in  return  errors  would  have  been  exhibited. 

Unlike  the  immediate  effect  of  the  control,  the  subsequent  in¬ 
fluence  upon  the  errors  amassed  per  trial  is  deleterious,  and  dele¬ 
terious  almost  without  exception.  Cul-de-sac  errors,  moreover, 
are  not  spared;  but  it  is  worthy  of  note  that  the  average  number 
of  cul-de-sac  errors  made  per  trial  in  the  post-control  period  does 
not,  in  general,  exhibit  so  large  a  relative  increase  over  the  normal 
as  do  the  return  errors.  No  very  regular  relation  is  apparent  in 
the  realm  of  cul-de-sac  errors  between  the  degree  of  relative  detri¬ 
ment  and  the  position  of  the  guided  series.  From  the  point  of  view 
of  the  return  errors  amassed  in  the  period  following  the  directed 


44 


HELEN  LOIS  KOCH 


trials,  the  initial  position  and  that  latest  in  the  trial  sequence  are 
the  least  detrimental. 

This  increase  in  errors  over  the  normal  in  the  human  records, 
as  contrasted  with  those  of  the  rats’,  is,  doubtless,  a  partial  result 
at  least,  of  the  fact  that  the  stylus  maze  entails  such  infinitely 
more  delicate  coordinations  than  does  the  large  maze  used  for 
the  animals  that  slight  alterations  are  far  more  disrupting  and  not 
readily  adjusted  to.  The  human  subject,  moreover,  was  not  in¬ 
formed  that  he  was  being  guided.  In  his  analyses,  undoubtedly, 
the  change  in  cues — when  it  is  consciously  recognized — is  inter¬ 
preted  as  the  result  of  a  false  tracing  or  the  entrance  into  regions 
yet  unexplored.  He  declares  himself  “lost."  A  re-examination  of 
the  whole  situation  is  attempted.  This  results,  in  the  case  of  the 
short  series,  in  much  vain  wandering  and  the  deleterious  habits  de¬ 
pendent  thereon.  It  must  be  remembered,  however,  that,  in  spite  of 
this  distracting  effect  of  the  control,  a  perfect  adjustment  to  the 
maze  situation  is  accomplished  in  fewer  trials  than  normally. 

Influence  upon  time  (Table  21)  :  The  effect  of  guidance  upon 
the  total  time  required  for  mastering  the  problem  is  positive  in  all 
cases  but  one.  The  benefit,  on  the  whole,  however,  is  very  slight. 
The  only  reduction  in  time  of  considerable  size  is  effected  by  con¬ 
trol  interpolated  late  in  the  trial  sequence. 

The  immediate  influence  of  directed  learning  upon  time  is,  in 
general,  favorable.  In  the  case  of  interpolated  guidance  there  is  a 
suggestion  of  a  tendency  for  the  relative  saving  in  time  during  the 
period  of  control  to  decrease  as  the  distance  of  the  directed  trials 
from  the  initial  run  is  increased.  The  same  tendency  was  present 
in  the  realm  of  return  errors.  Group  H2  (11-12),  in  the  case  of 
both  time  and  errors,  exhibits  a  marked  deviation  from  the  general 
trend. 

The  subsequent  effect  of  control  upon  the  time  consumed  per 
trial  is,  in  most  cases,  unfavorable,  or  so  slightly  favorable  that 
it  is  of  little  significance.  It  is  important  to  note,  however,  that 
guidance  occurring  within  the  first  six  trials  has  a  very  deleterious 
influence,  whereas  that  occurring  in  the  next  six  is  less  disturbing. 
The  reason  is  not  apparent.  It  is  possible  that  at  an  early  stage  of 
the  learning,  when  concepts  are  just  taking  form,  alteration  of 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


45 


TABLE  21.  INFLUENCE  OF  TWO  DIRECTED  TRIALS 
^  UPON  TIME— HUMAN  SUBJECTS 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

1573.69 

33-72 

2.10 

H2  (3-4) 

1569.12 

38.29 

2.38 

H 2  (5-6) 

175948 

— 152.07 

—9.46 

H2  (7-8) 

1587.92 

1949 

1.21 

H2  (9-10) 

1389.19 

218.22 

13-57 

H2  (11-12) 

1479.50 

127.91 

7.96 

B. 


Group 

Av.  Time 
per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

199.85 

50.40 

20.14 

H2  (3-4) 

61.31 

40.72 

39-91 

H2  (5-6) 

49-07 

2.92 

561 

H2  (7-8) 

38.42 

2.52 

6.22 

H2  (9-10) 

41.07 

—9.42 

— 29.76 

H2  (11-12) 

22.55 

8.81 

28.09 

C. 


Group 

Av.  Time  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

35-84 

— 11.04 

—44-52 

H2  (3-4) 

27.16 

— 4.16 

— 18.09 

H2  (5-6) 

27.79 

— 6.71 

—31-83 

H2  (7-8) 

19.22 

.69 

346 

H2  (9-10) 

20.43 

—1.63 

—8.67 

H2  (11-12) 

18.20 

—.28 

—1.56 

cues  has  a  retarding  effect  upon  speed.  After,  however,  a  general 
speed  set  has  been  established,  the  time  required  per  trial  may  be 
little  influenced  by  control.  In  fact,  the  slight  increase  in  time  ex¬ 
hibited  by  groups  H2  (9-10)  and  H2  (11-12)  in  the  post-control 
period  may  be  explained  in  terms  of  the  saving  in  trials  and  the 
consequent  reduction  in  the  practice  which  the  subject  gets  in  trac¬ 
ing  the  maze. 


46 


HELEN  LOIS  KOCH 


The  curves  reveal  nothing  that  is  not  adequately  depicted  in  the 
tables. 

Conclusion:  Control  has  a  positive  effect  upon  total  trials,  time 
and  errors,  when  it  is  interpolated  in  the  initial  and  latest  positions, 
but  is,  generally  speaking,  detrimental  in  the  intermediate  position. 
The  immediate  effect  of  guidance  is  to  reduce  return  errors  in 
the  early  trials  and  to  increase  them  above  the  normal  in  the  later. 
The  subsequent  effect  is  to  increase  time  and  both  types  of  error, 
but  the  degree  of  the  detriment  varies  in  no  consistent  way  with 
the  position  of  the  control. 

2.  Influence  of  Four  Directed  Trials  Introduced  at  Various 
Positions  in  the  Learning  Process 

As  in  the  experiment  in  which  rats  served  as  subjects,  so  here 
with  the  human  subjects,  a  group  was  guided  from  the  first  to  the 
fourth  run,  inclusive;  another,  from  the  fifth  to  eighth,  inclusive; 
a  third  group,  from  the  ninth  to  the  twelfth  run,  inclusive. 

TABLE  22.  INFLUENCE  OF  FOUR  DIRECTED  TRIALS 
UPON  TRIALS— HUMAN  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H4  (i-4) 

37-i 

7.2 

16.26 

H4  (5-8) 

437 

.6 

1.36 

H4  (9-12) 

37-5 

6.8 

15-35 

Influence  upon  trials  (Table  22)  :  The  influence  of  guidance 
extending  over  four  successive  runs  and  interpolated  as  described 
in  the  preceding  paragraph,  is  manifested  in  a  form  similar  to  that 
displayed  in  the  two-trial  series.  Initial  guidance  and  that  occur¬ 
ring  latest  in  the  trial  sequence  are  about  equally  effective  in 
reducing  the  number  of  trials;  whereas  the  influence  of  control 
in  the  intermediate  position  upon  trials  is  practically  negligible. 
So  considerable  a  deviation  from  the  results  of  the  experiment 
with  animals,  where  the  per  cent  of  saving  varies  inversely  as 
the  distance  of  the  guided  series  from  the  initial  trial,  is  signifi¬ 
cant.  It  is  possible,  as  we  have  previously  indicated,  that  in  the 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


47 


intermediate  stage  of  the  learning,  when  hypotheses  are  being 
formed,  a  limited  amount  of  control  is  very  confusing.  In  the 
later  trials,  when  the  subject  has  become  well  oriented,  the  con¬ 
trol,  even  though  causing  temporary  confusion  or  systematic  ex¬ 
plorations,  does,  after  all,  indicate  rather  forcibly  to  the  subject 
the  troublesome  elements  in  the  situation  and  facilitates  a  rapid 
adjustment. 

Influence  upon  errors  (Table  23)  :  The  effect  of  guidance, 
from  the  point  of  view  of  the  saving  accomplished  in  the  total 
number  of  errors  made,  varies  inversely  as  the  distance  of  the 
directed  series  from  the  beginning  of  the  learning.  The  control 
introduced  latest  proves  even  detrimental.  This  is  in  striking  con¬ 
trast  to  the  large  saving  in  trials  accomplished  by  the  control  thus 
interpolated.  A  probable  explanation  of  this  combination  of  effects 
was  indicated  in  the  discussion  of  the  influence  of  guidance  upon 
trials.  The  subject  may  be  puzzled  by  the  alteration  of  the  situa¬ 
tion,  incident  upon  the  introduction  and  removal  of  the  control, 
may  instigate  somewhat  systematic  explorations  and  make  many 
errors;  but  the  critical  elements  of  the  situation  have  been  called 
into  the  focus  of  his  attention  through  the  agency  of  the  guid¬ 
ing  device  and  conditions  are  ripe  for  a  ready  adjustment.  Control 
occurring  early  in  the  learning,  furthermore,  when  wandering  is 
prevalent,  has  many  more  opportunities  for  preventing  errors  than 
that  interpolated  later. 

The  ranking  of  the  groups  in  terms  of  the  per  cent  of  saving 
in  return  errors  during  the  period  of  control  is  the  same  as  that 
on  the  basis  of  total  errors.  The  ascendency  of  the  distracting 
phase  of  the  control’s  influence,  as  the  position  of  the  directed 
runs  is  well  removed  from  the  beginning,  is  again  evident;  i.e., 
the  return  error  scores  show  a  saving  which  varies  inversely  as  the 
distance  from  the  initial  trial  at  which  guidance  is  introduced.  The 
large  saving,  when  guidance  is  introduced  in  the  initial  trial,  is 
noticeably  contrary  to  the  findings  in  the  experiment  in  which 
rats  served  as  subjects.  The  probable  reason  for  the  difference  we 
have  suggested  in  our  discussion  of  the  effect  of  two  directed 
trials  upon  learning. 

The  subsequent  influence  of  the  control,  considered  both  from 


48 


HELEN  LOIS  KOCH 


A. 


TABLE  23.  INFLUENCE  OF  FOUR  DIRECTED  TRIALS 
UPON  ERRORS— HUMAN  SUBJECTS 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H4  (1-4) 

255-0 

138.7 

35-23 

H4  (5-8) 

378.5 

15-2 

3-86 

H4  (9-12) 

417.6 

—23-9 

— 6.07 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H4  (1-4) 

33-55 

4.36 

11.50 

H4  (5-8) 

8.30 

.67 

7-47 

H4  (9-12) 

5.8i 

— 1.06 

— 22.23 

C. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
in  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
( Per  Cent) 

H4  (1-4) 

1.38 

.16 

10.31 

H4  (5-8) 

1.68 

—•47 

—38.84 

H4  (9-12) 

1.63 

—  65 

— 66.32 

D. 


Group 

Av.No.of  Return 
Errors  per  Trial 
in  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H4  (i-4) 

1.80 

.60 

25.00 

H4  (5-8) 

1.84 

—.24 

—15.00 

H4  (9-12) 

2.92 

-1.58 

—1 17.91 

the  point  of  view  of  cul-de-sac  and  return  errors,  becomes  unfa¬ 
vorable,  as  the  position  of  the  guided  series  is  shoved  farther 
along  in  the  learning.  Guidance  in  the  initial  trials  has  a  positive 
subsequent  effect  upon  errors;  the  two  other  positions  result  in 
an  increase  in  errors  above  the  normal.  An  absolute,  as  well  as 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


49 


relative  increase  in  errors  per  trial  is,  in  general,  manifested,  the 
later  the  interpolation  of  the  directed  series.  The  large  positive 
saving  in  trials  for  group  H4  (9-12),  then,  becomes  very  signifi¬ 
cant,  since  it  indicates  that,  in  spite  of  a  great  disruption,  rapid 
adjustment  can  take  place. 

Since  in  the  records  based  on  the  performance  of  human  sub¬ 
jects  the  subsequent  effect  of  control  is  not  consistently  of  greater 
relative  magnitude  in  the  realm  of  cul-de-sac  than  return  errors, 
we  must  look  for  principles  other  than,  and,  perhaps,  less  mechan¬ 
ical  than,  the  one  of  repetition  which  we  used  to  explain  the  be¬ 
havior  of  rats.  Repetition  may  be  a  factor,  but  it  is  no  longer  the 
dominant  one  in  producing  the  results.  Ideational  control  is  a  pos¬ 
sible  factor.  After  an  individual  has  succeeded  in  attaining  the 
goal  several  times,  he  develops  an  idea  of  the  general  direction 
of  the  course  he  must  pursue.  When  cues  are  altered  and  explora¬ 
tion  follows,  the  reaction  is  likely  to  be  more  unfavorable — pro¬ 
vided  the  subject  does  not  become  badly  confused  or  completely 
lose  himself — upon  cul-de-sac  errors  than  upon  return  errors,  for, 
knowing  in  general  the  direction  in  which  the  goal  is  to  be  sought, 
the  subject  is  loath  to  turn  back  on  his  path. 

The  error  curves  do  little  more  than  confirm  the  tabular  evi¬ 
dence.  In  the  period  of  control,  the  curve  for  group  H4  (1-4) 
lies  well  below  the  normal,  whereas  in  the  post-control  period,  its 
general  course  differs  little  from  the  normal.  The  curve  of  group 
H4  (5-8)  (Figure  5),  on  the  other  hand,  exhibits  steeples  of 
medium  height  in  the  first  seven  trials  of  the  post-control  period, 
whereafter  it  follows  the  normal  rather  closely.  These  steeples 
carry  it  above  the  normal.  The  curve  for  group  H4  (9-12) 
(Figure  5)  has,  immediately  following  the  period  of  guidance, 
one  very  large  steeple  and  one  small  one  before  it  falls  rapidly 
and  regularly  to  about  the  level  of  the  normal  curve.  Its  subse¬ 
quent  course  is  slightly  irregular.  The  enormous  steeple  coincides 
with  what  we  have  previously  referred  to  as  the  period  of  some¬ 
what  systematic  exploration.  The  curves,  then,  indicate  longer 
wavering  and  less  rapid  adjustment  when  direction  is  given  in 
the  intermediate  position;  but  more  severe  and  shorter-lived  con¬ 
fusion,  when  control  is  introduced  late  in  the  learning. 


HELEN  LOIS  KOCH 


Fig.  5.  A  limited  section  of  the  error  curve  of  groups  H4  (5-8)  and 
H4  (9-12)  is  shown  superimposed  upon  the  error  curve  of  the  unguided  group. 
The  dashes  denote  the  unguided  group ;  the  dots,  the  guided  trials  of  the 
guided  groups ;  the  solid  line,  the  unguided  trials  of  the  guided  groups. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


5i 


Influence  upon  time  (Table  24)  :  The  scores  indicating  the  total 
time  required  by  the  guided  groups  to  master  the  problem  exhibit 
only  a  slight  saving  over  the  time  scores  of  the  normal  group. 
The  immediate  effect  of  the  control  in  all  positions  is  a  positive 
saving,  and  the  initial  position  seems  the  most  favorable  condition. 
The  time  per  trial  for  the  trials  of  the  post-control  period  is,  on 
the  other  hand,  in  the  case  of  each  directed  group,  in  excess  of  the 
normal.  The  increase  in  time,  over  that  of  the  normal,  manifested 
by  Group  H4  (1-4),  in  spite  of  the  decrease  in  errors,  is  sig¬ 
nificant. 

The  time  curves  in  their  relation  to  the  normal  in  the  post-con¬ 
trol  period  resemble  the  error  curves  so  closely,  a  discussion  of 
them  will  be  of  no  value. 

Conclusion :  In  general,  the  effect  of  guiding  four  of  the  trials 
results  in  a  slight  but  positive  saving  in  the  realm  of  total  trials, 
total  time  and  total  errors.  The  immediate  effect  upon  return  er¬ 
rors  varies  inversely  as  the  distance  of  the  directed  runs  from  the 
initial  trial.  This  same  inverse  relationship  between  errors  and 
the  distance  of  the  period  of  guidance  from  the  initial  stage  of  the 
learning  holds  for  all  of  the  error  scores  of  the  post-control 
period,  as  well  as  for  the  total  number  of  errors  amassed  during 
the  complete  learning  process.  The  intermediate  position  is  least 
favorable  to  a  reduction  in  trials,  most  favorable  to  a  reduction  in 
total  time.  The  initial  and  final  positions  have  about  the  same 
value,  so  far  as  these  latter  two  measures  are  concerned.  The  im¬ 
mediate  effect  is  to  decrease  the  time;  the  subsequent  effect  is  to 
increase  the  time  consumed  per  trial. 


52 


HELEN  LOIS  KOCH 


A. 


TABLE  24.  INFLUENCE  OF  FOUR  DIRECTED  TRIALS 
UPON  TIME— HUMAN  SUBJECTS 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H4  (1-4) 

1548.63 

58.78 

3-  66 

H4  (5-8) 

1597.22 

10.19 

0.63 

H4  (9-12) 

1566.48 

40.93 

2.57 

B. 


Group 

Av.  Time 
per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H4  (1-4) 

149.92 

17.60 

10.50 

H4  (5-8) 

42.17 

3.63 

7.09 

H4  (9-12) 

32.73 

346 

9-57 

C. 


Group 

Av.  Time  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H4  (i-4) 

28.55 

—5-55 

— 24.12 

H4  (5-8) 

22.90 

—2.99 

—15.02 

H4  (9-12) 

21.77 

—3-85 

— 21.48 

3.  Influence  of  Six  Directed  Trials  Introduced  at  Various 
Positions  in  the  Learning  Process 

Only  two  groups  of  human  subjects  were  granted  series  of  six 
directed  trials.  One  group  was  guided  from  the  first  to  the  sixth 
trial,  inclusive;  the  other  group,  from  the  seventh  to  the  twelfth 
run,  inclusive. 

Influence  upon  trials  (Table  25)  :  Unlike  the  groups  guided  for 
the  initial  two  or  four  trials,  the  saving  in  trials  for  group 
H6  (1-6)  is  practically  negligible,  and  is  far  exceeded  by  the  sav¬ 
ing  in  the  group  guided  in  the  later  trials.  The  apparent  ineffective¬ 
ness,  so  far  as  trials  are  concerned,  of  control  doled  out  during  the 
initial  six  runs,  is  significant,  especially  since,  in  the  experiment 
conducted  upon  the  rats,  control  in  the  initial  six  trials  was  the 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


53 


TABLE  25.  INFLUENCE  OF  SIX  DIRECTED  TRIALS 
UPON  TRIALS— HUMAN  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H6  (1-6) 

43-6 

•7 

1.58 

H 6  (7-12) 

37-1 

7-2 

16.24 

most  favorable  condition  for  learning.  Again  we  seem  forced  to 
seek  an  explanation  in  ideational  terms.  The  six-trial  series  is  ap¬ 
parently  sufficiently  long  to  permit  the  subject  to  develop  a  vague 
concept  of  the  maze  and  a  fair  amount  of  confidence  in  his  own 
procedure.  When  he  does  go  astray,  upon  the  removal  of  the  con¬ 
trolling  device,  an  emotional  tone  in  the  form  of  a  feeling  of  dis¬ 
couragement  becomes  very  pronounced  and  a  vain  search  for  the 
lost  cues  is  instigated.  This  search,  with  its  unsatisfied  desire, 
tends  to  hinder  a  rapid  and  complete  adjustment  to  the  maze  situa¬ 
tion. 

The  same  explanation  for  the  saving  in  group  H6  (7-12)  as 
was  advanced  to  account  for  the  reduction  in  the  number  of  trials 
required  for  learning  in  group  H4  (9-12),  may  be  offered.  Repe¬ 
tition  of  the  discussion  is  unnecessary. 

Influence  upon  errors  (Table  26)  :  Although  the  adjustment 
is  slower  in  the  case  of  group  H6  (1-6)  than  in  group  H6  (7-12), 
the  saving  in  total  errors  is  considerably  greater.  This  saving,  an 
inspection  of  the  records  reveals,  is  a  result  of  the  immediate 
physical  effect  of  the  control,  and  of  control  in  the  very  early  trials, 
especially. 

The  negative  saving  in  the  number  of  return  errors  accumu¬ 
lated  during  the  period  of  control  by  group  H6  (1-6),  in  contrast 
to  the  positive  saving  exhibited  by  group  H6  (7-12),  is  significant. 
It  is  probably  indicative  of  the  operation  of  the  same  factors  which 
produced  the  accentuation  of  the  retracing  reaction  in  the  case  of 
the  animal  groups  guided  for  the  initial  two,  four  and  six  trials. 
Wandering  characterizes  the  early  stage  of  the  learning.  As  soon 
as  some  familiarity  with  the  maze  is  attained  and  the  turns  of  the 
true  path  no  longer  act  as  barriers,  the  exploratory  activities  on 


54 


HELEN  LOIS  KOCH 


A. 


TABLE  26.  INFLUENCE  OF  SIX  DIRECTED  TRIALS 
UPON  ERROR— HUMAN  SUBJECTS 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H6  (1-6) 

334-8 

58.9 

14.96 

H6  (7-12) 

380.3 

13-4 

3-40 

B. 


Av.  No.  of  Return 

Group 

Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H6  (1-6) 

30.52 

—3-76 

—12.32 

H6  (7-12) 

3-95 

1-35 

25.61 

C. 


» 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

H6  (1-6) 

i-75 

—•44 

—33-59 

H6  (7-12) 

1. 16 

— .18 

—18.36 

D. 


Av.  No.  of  Return 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

H6  (1-6) 

3-53 

—1.68 

— 90.81 

H6  (7-12) 

1-45 

— .11 

— 8.21 

the  part  of  the  guided  subjects  manifest  themselves  largely  in 
long  retracings  which  are  unhampered  by  entrances  into  cul-de- 
sacs,  as  in  the  case  of  the  unguided  subjects. 

Normally,  the  early  stages  of  the  learning  are  characterized  by 
a  rapid  decline  in  return  errors.  The  subject  develops  a  notion  of 
the  general  direction  of  the  goal  and  some  confidence  in  his  pro¬ 
cedure.  Consequently,  when  control  is  interpolated  after  the  sixth 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


55 


trial,  the  simplification  of  the  maze  pattern  operates  principally  to 
decrease  below  the  normal  the  retracings. 

The  subsequent  effect  upon  errors  is  negative  in  both  types  of 
error,  thus  indicating  that  the  distraction  resulting  from  alteration 
of  cues  rather  than  any  beneficial  effect  of  the  control  is  dominant. 
Group  H6  (1-6)  suffers  more  than  group  H6  (7-12). 

The  error  curve  for  group  H6  (1-6)  (Figure  6)  through  prac¬ 
tically  its  entire  course  lies  above  the  normal.  Immediately  subse¬ 
quent  to’  the  guided  trials  a  very  large  steeple  appears.  This  is 
followed  by  a  sudden  drop  in  the  curve  and  a  series  of  smaller 
steeples  whose  general  level  is  considerably  below  that  of  the  first 
steeple,  but  still  somewhat  above  the  normal  curve.  These  irregu¬ 
larities  persist  for  about  twenty  trials.  The  curve  drops  to  the 
normal  level  at  about  the  thirty-sixth  trial.  The  curve  for  group 
H6  ( 7-12 )  (Figure  6),  on  the  other  hand,  lies  below  the  normal 


TABLE  27.  INFLUENCE  OF  SIX  DIRECTED  TRIALS 

UPON  TIME— HUMAN  SUBJECTS 
A. 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H 6  (1-6) 

1705.75 

—98.34 

— 6.12 

H 6  (7-12) 

1571.79 

35-62 

2.22 

B. 


Av.  Time 

Group 

per  Directed 

Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H6  (1-6) 

136.74 

— 21.12 

— 18.27 

H6  (7-12) 

25.90 

11.96 

31-59 

C. 


Av.  Time  per  Trial 

Group 

for  Trials 

Absolute  Saving 

Relative  Saving 

Subsequent  to  Control 

(Per  Cent) 

H6  (1-6) 

27.27 

— 6.19 

— 29.36 

H6  (7-12) 

22.48 

—4-56 

—25-45 

THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


57 


in  the  control  period  and  exhibits  small  steeples  with  a  generally 
rising  level  in  the  first  twelve  trials  of  the  post-control  period.  Like 
the  preceding  curve,  it  joins  the  normal  at  about  the  thirty-eighth 
trial. 

Since  the  time  scores  reveal  nothing  very  significant,  we  shall 
forego  a  discussion  of  them. 

Conclusion :  Six  directed  trials  result  in  a  small  saving  in  both 
trials  and  total  errors.  The  immediate  effect  of  initial  control  is 
to  increase  the  return  errors  above  the  normal;  whereas  that  of 
interpolated  control  is  to  decrease  the  return  errors.  The  subse¬ 
quent  effect  of  the  guidance  is  to  increase  above  the  normal  the 
time  and  errors  per  trial. 

4.  Influence  of  Eight  Directed  Trials  Introduced  at  Various 
Positions  in  the  Learning  Process 

Series  of  eight  successive  guided  trials  were  introduced  upon 
the  first  and  upon  the  ninth  trial. 

TABLE  28.  INFLUENCE  OF  EIGHT  DIRECTED  TRIALS 
UPON  TRIALS— HUMAN  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H8  (1-8) 

574 

— 13. 1 

—29.58 

H8  (9-16) 

37-i 

7.2 

16.36 

Influence  upon  trials  (Table  28)  :  Guidance  in  the  initial  runs 
increases  above  the  normal  the  trials  required  to  learn  the  maze, 
whereas  control  interpolated  late  reduces  the  number  of  trials  con¬ 
siderably.  The  scores  agree  well  with  the  general  tendency  mani¬ 
fested  in  the  case  of  the  six-trial  groups,  and  must  be  accounted 
for  upon  the  same  principles.  The  tendency,  on  the  contrary,  dif¬ 
fers  radically  from  that  observed  in  the  case  of  the  animals. 

Influence  upon  errors  (Table  29)  :  Both  groups  exhibit  a  posi¬ 
tive  saving  in  the  total  number  of  errors  made.  Group  H8  (9-16), 
although  requiring  fewer  trials  than  group  H8  (1-8),  nevertheless 
ranks  second  in  merit,  when  the  total  number  of  errors  accumu- 


58 


HELEN  LOIS  KOCH 


A. 


TABLE  29.  INFLUENCE  OF  EIGHT  DIRECTED  TRIALS 
UPON  ERRORS— HUMAN  SUBJECTS 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H8  (1-8) 

326.4 

67.3 

17.09 

H8  (9-16) 

362.7 

31.0 

7.87 

B. 


Av.  No.  of  Return 

Group 

Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H8  (1-8) 

19.76 

0.00 

0.00 

H8  (9-16) 

1.70 

1.81 

51-57 

C. 


Av.  No.  of  Cul-de-Sac 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

H8  (1-8) 

1.28 

—.07 

—5-79 

H8  (9-16) 

103 

—.24 

—30.38 

D. 


Av.  No.  of  Return 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(PerCent) 

H8  (1-8) 

1-57 

.03 

1.88 

H8  (9-16) 

2.16 

—.86 

—66.15 

lated  is  used  as  a  measure.  The  greater  efficacy  of  initial  guidance 
in  reducing  the  total  number  of  errors  was  apparent,  also,  in  the 
case  of  the  six-trial  series.  It  is,  doubtless,  the  result  largely  of 
no  subtler  agency  than  the  physical  prevention  of  cul-de-sac  er¬ 
rors  during  the  extended  wanderings  which  characterize  the  early 
runs. 

The  immediate  influence  of  guidance,  however,  upon  return 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


59 


errors  is  relatively  greater  in  the  case  of  group  H8  (9-16)  than 
group  H8  (1-8).  Barring  from  consideration  the  fact  that  an  in¬ 
crease  in  return  errors  is  not  exhibited  by  group  H8  (1-8),  one 
can  note  a  striking  resemblance  in  regard  to  the  relation  of  the 
immediate  effect  of  control  granted  early  and  late  in  the  learning, 
between  the  six-  and  eight-trial  series.  The  absence  of  an  increase 
in  return  errors  in  the  case  of  group  H8  (1-8),  as  contrasted  with 
group  H6  (1-6),  is,  doubtless,  the  result  of  the  interaction  of  a 
number  of  factors a  saving  in  the  very  early  trials,  a  loss  in 
the  few  trials  following  these  early  runs  (both  of  these  we  have 
previously  described),  and  a  saving  again,  perhaps,  in  the  seventh 
and  eighth  trials,  as  a  result  of  the  conquest  of  the  retracing  habit. 
A  counterbalancing  of  factors,  rather  than  the  absence  of  any  in¬ 
fluence,  produces  the  score  in  return  errors  which  exactly  equals 
the  normal. 

The  general  effect  upon  the  errors  made  per  trial  in  the  post¬ 
control  period  is  deleterious,  but  only  decidedly  so  when  guidance 
is  given  late  in  the  learning.  Let  it  be  noted  that,  in  spite  of  the 
increase  in  errors,  the  number  of  trials  required  by  group 
H8  (9-16)  is  less  than  that  required  by  group  H8  (1-8)  or  the 
normal  group. 

The  curves  give  some  interesting  data  upon  the  nature  and  per¬ 
sistence  of  the  control’s  influence  not  revealed  in  the  tables.  For 
seven  trials  immediately  following  the  removal  of  the  guiding  de¬ 
vice  the  curve  for  group  H8  (1-8)  runs  along  rather  regularly, 
considerably  below  the  level  of  the  normal  curve.  Then  follows  a 
period  of  large  steeples  extending  over  about  nine  trials,  where¬ 
after  the  curve  descends  irregularly  and  slightly  above  the  normal. 

This  apparent  occurrence  of  great  confusion  considerably  after 
the  period  of  control  seems  typical  of  the  groups  directed  for  long 
periods  in  the  early  stages  of  the  learning,  for  the  group  guided 
during  the  initial  twelve  trials  reveals  a  similar  tendency  (Figure 
4).  The  phenomenon  can  be  easily  explained.  Much  control  early 
in  the  learning  builds  up  confidence  and  well  established  habits. 
The  confidence  is  sufficient  to  create  indifference  with  respect  to 
the  slight  suspicions  aroused  by  the  altered  cues  which  attend  the 
removal  of  the  controlling  device.  These  suspicions  grow,  in  the 


6o 


HELEN  LOIS  KOCH 


trials  that  follow,  because  the  strangeness  persists.  Then  chance 
entrances  into  cul-de-sacs  reveal  a  multitude  of  possibilities  to  the 
unsuspecting  subject  who  seeks  in  them  new  and  shorter  routes 
to  the  goal.  He  becomes  confused  and  almost  hopelessly  lost.  Long 
after  a  readjustment  is  well  afoot,  waverings  are  apparent.  Hence 
the  reason  for  the  irregularity  of  the  curve  in  its  final  stages  is  ap¬ 
parent. 

The  curve  for  group  H8  (9-16)  in  the  post-control  period  is 
not  very  dissimilar  to  that  of  group  H8  (1-8).  A  small  steeple 
follows  immediately  the  control  period,  then  a  low  course  is  main¬ 
tained  for  seven  trials,  whereupon  a  decided  rise  (larger  than  any 
previous  steeple)  persists  for  four  trials.  The  later  sections  of  the 
curve  are  more  irregular  than  the  normal.  The  disturbance  is  ap¬ 
parently  not  so  great  when  guidance  occurs  later  in  the  learning, 
as  it  is  when  control  is  granted  in  the  early  runs.  The  phenomenon 
is  probably  the  result  of  the  fact  that  the  reagent  has  had  some  pre¬ 
vious  experience  with  the  cul-de-sacs,  knows  a  little  concerning 
their  fatal  character,  and  seeks  not  within  them,  with  much  fervid 
conviction,  the  desired  short  route. 

The  irregularity  of  both  curves  in  the  post-control  period  re¬ 
flects  the  persistent  doubt  and  uncertainty  resulting  from  the  con¬ 
flict  of  two  rather  well  established  forms  of  reaction. 

Conclusion :  Guidance  extending  over  the  initial  eight  trials 
tends  to  increase  above  the  normal  the  number  of  trials  and  the 
total  time  required;  control  in  the  later  runs  reduces  both  trials 
and  time.  Both  the  initial  and  interpolated  guidance  accomplish  a 
saving  in  total  errors,  the  saving  being  greater  in  the  case  of  initial 
control.  The  immediate  effect  of  control  is  positive  in  the  case  of 
both  time  and  errors,  whether  guidance  be  given  early  or  late  in 
the  learning  period,  but  relatively  greater  when  control  is  given 
late.  The  subsequent  effect  of  guidance  is  to  increase  above  the 
normal  the  number  of  errors  made  per  trial.  The  negative  saving 
in  errors  per  trial  in  the  post-control  period  is  greater  when  con¬ 
trol  is  interpolated  late  in  the  trial  sequence  than  when  it  occurs 
early. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


61 


A. 


TABLE  30.  INFLUENCE  OF  EIGHT  DIRECTED  TRIALS 
UPON  TIME— HUMAN  SUBJECTS 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H8  (1-8) 

1563-03 

44.38 

2.76 

H8  (9-16) 

1554.15 

63.26 

3-94 

B. 


Av.  Time 

Group 

per  Directed 

Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H8  (1-8) 

74-58 

7.62 

9.27 

H8  (9-16) 

24.31 

5-68 

18.94 

C. 


Av.  Time  per  Trial 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H8  (1-8) 

17.98 

1.93 

9.69 

H8  (9-16) 

21.21 

—4-52 

— 27.08 

SUMMARY 

A.  Results  of  Experimentation  upon  Animals : 

1.  The  efficacy  of  a  given  number  of  guided  trials  is  a  function 
of  their  position. 

2.  The  efficacy  of  the  control  as  an  agent  for  reducing  the 
number  of  trials  required  to  master  the  problem  varies,  as  a  rule, 
inversely  as  the  distance  of  the  guided  series  from  the  initial 
trial. 

3.  The  influence  of  guidance  in  the  realm  of  total  errors  is 
beneficial ;  but,  in  general,  as  the  distance  of  the  guided  series  from 
the  initial  trial  increases,  the  total  number  of  errors  increases. 
When  the  directed  series  is  very  short,  however,  the  intermediate 
position  is  the  most  favorable  and  it  is  only  slightly  less  favorable 
than  the  initial  position  when  the  series  are  of  medium  length. 


62 


HELEN  LOIS  KOCH 


4.  The  immediate  effect  of  control  is  to  prevent  cul-de-sac  er¬ 
rors.  The  number  prevented  varies  inversely  as  the  distance  of  the 
series  of  directed  trials  from  the  initial  run,  and  directly  as  the 
length  of  the  series.  The  explanation  of  the  fact  harks  back  to  the 
nature  of  the  learning  process. 

5.  The  relative  saving  in  the  number  of  return  errors  amassed 
during  the  period  of  control  which  occurs  in  an  intermediate  posi¬ 
tion  is  always  positive  and,  in  general,  greater  than  for  any  other 
position. 

6.  Short  series  of  guided  trials  in  the  initial  position  increase 
above  the  normal  the  number  of  return  errors  made  in  the  period 
of  guidance,  whereas  the  longer  series  in  the  same  position  result 
in  a  saving  in  return  errors. 

7.  The  immediate  effect  of  control  in  the  position  most  distantly 
removed  from  the  beginning  is  not  entirely  unambiguous;  i.e.,  a 
reduction  in  return  errors  may  or  may  not  be  effected.  In  general, 
however,  the  relative  saving  is  less  than  that  accomplished  by  con¬ 
trol  in  the  intermediate  position. 

The  results  indicating  the  immediate  effect  of  guidance  are  the 
outcome  of  the  interaction  of  factors  both  detrimental  and  advan¬ 
tageous.  It  seems  well,  even  at  the  risk  of  accusations  of  prolixity, 
to  summarize  the  factors  suggested  to  account  for  the  records 
made  during  the  period  of  control. 

The  increase  above  the  normal  of  the  return  errors  amassed  per 
trial  in  the  shorter  periods  of  control  in  the  initial  position,  we 
have  attempted  to  explain  on  the  basis  of  the  facilitation  of  com¬ 
plete  retracings  resulting  from  the  absence  of  cul-de-sacs.  This 
deleterious  effect  upon  return  errors  is  balanced  in  the  longer 
series  by  the  rapid  attainment  of  a  well-nigh  complete  mastery  of 
the  simple  cul-de-sac-less  maze  and  the  consequent  almost  total 
elimination  of  the  retracing  errors  in  the  later  trials  of  the  series. 
In  positions  other  than  the  initial,  the  immediate  influence  of  the 
control  upon  return  errors  is  the  result  of  a  balance  between  the 
benefit  derived  from  the  prevention  of  cul-de-sacs,  and  simplifica¬ 
tion  of  the  problem,  on  the  one  hand,  and  confusion  or  distraction 
attendant  upon  the  alteration  of  cues  already  integrated  into  habits 
of  various  degrees  of  strength,  on  the  other.  The  detrimental 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE  63 

phase  of  the  control’s  influence  is  on  the  ascendency,  though  not 
always  dominant,  in  those  positions  of  the  directed  trials  most 
distantly  removed  from  the  beginnings  of  the  learning. 

8.  The  saving  in  the  number  of  cul-de-sac  errors  made  per  trial 
in  the  post-control  period  is,  with  one  exception,  positive  and  is, 
generally,  greater  than  the  saving  in  return  errors. 

9.  The  subsequent  effect  of  a  small  amount  of  guidance  (two 
or  four  trials)  upon  cul-de-sac  errors  is  relatively  greatest  in  the 
case  of  the  groups  whose  period  of  control  was  introduced  in  an 
intermediate  position,  whereas  the  subsequent  effect  of  larger 
amount  is  the  most  favorable  when  guidance  occurs  in  the  initial 
position. 

10.  The  number  of  return  errors  amassed  per  trial  in  the 
post-control  period  by  the  groups  given  short  periods  of  initial 
guidance  or  short  periods  of  control  introduced  late  in  the  learn¬ 
ing  is  greater  than  that  amassed  by  the  normal  group.  The  inter¬ 
mediate  position  is  most  favorable  or  least  unfavorable  in  its  sub¬ 
sequent  effect  upon  return  errors  when  the  period  of  guidance 
is  limited;  the  initial  position  is  the  most  favorable  when  the 
period  of  control  is  rather  extended. 

The  subsequent  effect  of  control  is  a  balance  between  the  benefit 
resulting  from  the  formation  of  proper  habits,  the  prevention  of 
the  formation  of  undesirable  reactions,  the  marking  of  the  critical 
elements  in  the  situation,  on  the  one  hand,  and  the  confusion  at¬ 
tendant  upon  the  alteration  of  cues,  on  the  other.  A  very  limited 
amount  of  guidance  in  an  intermediate  position,  when  habits  are 
plastic,  merely  calls  attention  to  the  critical  elements  of  the  situa¬ 
tion  and  enters  little  into  conflict  with  well  established  modes  of 
behavior.  Control  interpolated  late  in  the  learning  may  enter  into 
conflict  with  reactions  to  the  maze  that  have  been  thoroughly  in¬ 
grained. 

11.  Control  usually  results  in  a  reduction  in  total  time.  The 
amount  of  reduction  tends  to  vary  inversely  as  the  distance  (with¬ 
in  limits)  of  the  directed  trials  from  the  initial  run. 

12.  The  immediate  effect  of  guidance  upon  time  is,  in  most 
cases,  positive  and  is  relatively  greatest  when  control  is  introduced 
in  the  intermediate  positions.  The  time  per  directed  trial,  when  the 


64 


HELEN  LOIS  KOCH 


series  is  short  and  interpolated  late  in  the  learning,  is  greater  than 
the  normal. 

13.  The  subsequent  effect  of  little  guidance  upon  the  time  con¬ 
sumed  per  trial  is  unfavorable.  The  intermediate  position  is,  gen¬ 
erally  speaking,  the  least  detrimental  or  the  most  favorable  in  its 
influence.  Long  periods  of  control  tend  to  reduce  the  time  per 
trial  in  the  post-control  period,  especially  when  guidance  occurs 
in  the  initial  runs. 

B.  Results  of  the  Experimentation  upon  Human  Subjects : 

1.  The  efficacy  of  a  given  amount  of  control  is  conditioned  by 
the  position  in  the  learning  at  which  it  is  introduced. 

2.  Control,  if  properly  placed,  accomplishes  a  reduction  in  the 
number  of  trials  necessary  for  learning  the  maze.  Generally  speak¬ 
ing,  its  efficacy  varies  directly  as  its  distance  from  the  early  trials. 
The  exception  to  the  general  rule  occurs  in  the  case  of  short  peri¬ 
ods  of  initial  guidance  which  are  equal  in  effectiveness  to  periods 
of  similar  length  interpolated  later  in  the  learning. 

The  divergence  of  these  results  from  those  derived  in  the  ex¬ 
perimentation  upon  animals  we  have  accounted  for  largely  in  terms 
of  ideational  control.  When  the  reaction  to  the  situation  has  so 
shaped  itself  that  the  alteration  of  cues  can  be  recognized  with 
some  confidence  and  attention  can  be  consciously  directed  to  the 
critical  elements  of  the  situation,  then  guidance,  though  causing 
exploration,  may  be  effective  in  bringing  about  a  rapid  adjust¬ 
ment.  The  modification  of  the  cues  in  the  trials  immediately  fol¬ 
lowing  the  first  few  merely  counteracts  the  favorable  aspects  of 
the  control’s  influence  by  injecting  confusion  into  a  reaction  which 
is  just  losing  its  polymorphic  character.  Little  guidance  in  the 
initial  position  is  beneficial  because  it  does  prevent  the  formation 
of  some  unfavorable  habits  and  is  withdrawn  before  cues  depend¬ 
ent  upon  it  are  integrated  with  any  fixity  into  the  sensory  and 
ideational  content. 

3.  The  effect  of  control,  measured  in  terms  of  total  errors,  is 
usually  favorable  and,  generally  speaking,  varies  directly  with  the 
distance  of  the  guided  trials  from  the  initial  runs.  The  exception 
to  this  general  rule  occurs  in  the  case  of  very  little  guidance  ad- 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


65 


ministered  rather  late  in  the  learning  process.  This  condition  is 
very  efficacious. 

4.  The  rapidity  of  adjustment  may  vary  independently  of  the 
total  number  of  errors  accumulated. 

5.  The  immediate  effect  of  control  is,  in  most  cases,  favorable. 
The  relative  saving  in  return  errors  effected  by  the  longer  groups 
of  guided  trials  varies  directly  with  the  distance  of  the  controlled 
runs  from  the  initial  trial.  The  reverse  is  true  for  the  short  series. 

The  saving  in  the  number  of  return  errors  amassed  during  the 
period  of  control,  when  the  directed  runs  are  few  and  occur  in 
the  early  trials,  we  have  attempted  to  account  for  on  the  basis  of 
the  simplification  in  the  problem  which  results  from  the  absence  of 
cul-de-sacs,  as  well  as  the  improbability  of  complete  retracings  be¬ 
cause  of  the  barrier-like  character,  in  the  early  stages  of  the  learn¬ 
ing,  of  the  turns  in  the  true  pathway.  Little  guidance  later  in  the 
learning,  on  the  other  hand,  has  a  deleterious  immediate  effect 
because  it  alters  cues  well  integrated  into  the  individual’s  reactions 
and  it  is  not  sufficiently  extended  to  permit  an  effective  readjust¬ 
ment  to  the  modified  situation.  The  longer  groups  of  directed 
trials,  interpolated  late,  permit  this  almost  complete  readjustment 
with  its  resultant  benefit. 

A  possible  explanation  of  the  increase  in  return  errors  per  di¬ 
rected  trial  when  the  period  of  initial  guidance  is  rather  extended, 
has  been  hinted  at  in  the  preceding  discussion.  As  soon  as  the  bar¬ 
rier-like  effect  of  the  turns  in  the  true  pathway  has  been  overcome 
* — and  this  occurs  early  in  the  learning — control  tends  temporarily 
to  facilitate  retracings. 

6.  The  subsequent  effect  of  guidance  upon  cul-de-sac,  as  well 
as  upon  return  errors,  is  usually  detrimental,  although  the  degree 
of  detriment  varies  in  no  consistent  way  with  the  position  of  the 
control. 

7.  Control,  in  its  subsequent  effect  upon  errors,  is  not  selective, 
as  it  was  in  the  case  of  the  animals.  Its  influence  is  as  unfavorable 
upon  cul-de-sac  as  upon  return  errors. 

The  subsequent  effect  of  control  we  have  attempted  to  describe 
as  a  resolution  of  the  influences  of  such  unfavorable  factors  as 
the  distraction  attendant  upon  the  removal  of  the  controlling  de- 


66 


HELEN  LOIS  KOCH 


vice,  the  retracing  habit  established  in  the  period  of  control,  and 
voluntary  explorations  concomitant  with  elaborate  analyses,  on 
the  one  hand,  and  the  effects  of  such  favorable  factors  as  the 
formation  of  proper  habits  and  bringing  to  the  attention  of  the 
subject  the  critical  elements  of  the  situation,  on  the  other.  The 
former  group  are  usually  dominant. 

The  assumption  of  a  relatively  analytical  mode  of  attack  on 
the  problem  by  the  human  subjects,  in  contrast  to  the  animal, 
seems  not  an  unreasonable  partial  explanation,  at  least,  of  the  dif¬ 
ferences  in  the  behavior  of  the  two  groups.  The  method  of  dis¬ 
tributing  effort  in  the  two  experiments,  moreover,  may  also  have 
been  no  small  factor  in  producing  the  variations  in  the  results. 
The  question  needs  experimental  investigation. 

8.  The  effect  of  control  upon  the  total  time  required  to  master 
the  problem  is  slight  but  usually  favorable.  The  time  scores  for 
the  period  of  control  vary  with  the  position  of  the  guided  trials  in 
about  the  same  way  as  do  the  error  scores.  The  subsequent  effect 
of  control  upon  time  is  not  sufficiently  regular  in  its  manifesta¬ 
tions  to  permit  a  generalization. 


Ill 

THE  RELATIVE  EFFICACY  OF  VARIOUS 
AMOUNTS  OF  CONTROL 

It  is  the  purpose  of  this  chapter  to  present  a  description  and 
analysis  of  the  influence  upon  learning  of  various  amounts  of 
guided  effort.  Although  it  is  obviously  impossible  to  separate  en¬ 
tirely  the  influence  of  the  amount  from  the  influence  of  the  posi¬ 
tion  of  the  guidance,  it  seems  desirable,  nevertheless,  to  compare 
the  behavior  of  those  groups  of  animals  which  have  had  the  same 
amount  of  preparation  previous  to  the  period  of  control. 

A.  Results  Based  upon  the  Records  of  Animal  Subjects 

The  investigation  in  which  animals  served  as  subjects  produced 
few  data  relevant  to  the  topic  of  this  chapter  other  than  those 
which  will  furnish  a  basis  for  a  consideration  of  the  question  of 
the  relative  effectiveness  of  various  amounts  of  initial  guidance. 
A  comparison,  however,  of  the  influence  of  series  of  four  and 
eight  directed  trials  introduced  upon  the  fifth  run,  is  possible. 

i.  The  Influence  of  Various  Amounts  of  Initial  Guidance 

Let  it  be  recalled  that  groups  2(1-2),  4(1-4),  6(1-6), 
8  (1-8),  and  12  (1-12)  were  guided,  respectively,  for  the  initial 
2,  4,  6,  8,  or  12  trials.  A  consideration  of  the  behavior  of  these 
groups  will  constitute  the  programme  of  this  section. 

Influence  'upon  trials :  Guidance  in  the  initial  position,  regard¬ 
less  of  the  amount,  is  effective  in  reducing  the  number  of  trials 
necessary  to  attain  a  mastery  of  the  maze  (see  Table  31).  The 
efficacy  of  the  control,  however,  increases  as  the  amount  of  guid¬ 
ance  is  increased  from  two  to  six  trials,  but  decreases  again  as 
the  length  of  the  guided  series  is  extended  to  eight  and  twelve 
runs.  In  other  words,  there  is  an  optimum  amount  of  guidance 
beyond  which  the  efficacy  of  the  control  decreases  rapidly. 


67 


68 


HELEN  LOIS  KOCH 


TABLE  31.  INFLUENCE  UPON  TRIALS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  IN  THE  INITIAL  POSITION— ANIMAL  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

25-5 

8.3 

24.6 

4  (i-4) 

22.0 

11.8 

34-9 

6  (1-6) 

15.5 

18.3 

54.14 

8  (1-8) 

19.9 

13.9 

41.12 

12  (1-12) 

24.1 

9-7 

28.69 

Influence  upon  errors :  The  relative  efficacy  of  various  amounts 
of  control  in  the  initial  position  is  the  same  in  the  realm  of  total 
errors  as  in  the  realm  of  trials  (see  Table  32).  The  per  cent  of 
saving  increases  as  the  number  of  directed  trials  is  increased  to 
six,  and  decreases  slightly  when  more  than  six  controlled  runs  are 
given. 

The  immediate  effect  of  various  amounts  of  guidance  in  the 
initial  position  upon  the  number  of  return  errors  made  per  trial 
we  have  already  briefly  indicated  in  the  previous  chapter.  The  in¬ 
fluence  of  little  control  upon  the  number  of  return  errors  made 
per  directed  run  is  deleterious,  and  the  degree  of  detriment  in¬ 
creases  as  the  length  of  the  guided  series  is  extended  from  two  to 
six  runs.  More  than  six  directed  trials,  however,  effect  a  reduction 
in  the  number  of  return  errors  amassed  per  trial  during  the  period 
of  control. 

Since  the  scores  indicating  the  immediate  effect  of  control  in 
each  series  are,  in  part,  based  upon  the  records  of  all  of  the  series 
shorter  in  length,  the  relative  influence  of  each  two  successive 
trials  of  the  first  twelve  runs  can  be  demonstrated  or  inferred 
from  the  average  scores  given.  Control  in  the  first  two  trials  is 
unfavorable  to  the  reduction  of  return  errors.  This  result  we  have 
attempted  to  explain  on  the  basis  of  the  facilitation  of  complete 
retracings  by  the  prevention  of  cul-de-sac  errors.  Guidance  in 
the  third  and  fourth  trials  is  relatively  more  unfavorable  to  the 
reduction  of  return  errors  than  in  the  first  two  runs,  while  control 
in  the  fifth  and  sixth  trials  accomplishes  the  most  marked  rela¬ 
tive  increase  in  the  number  of  retracings.  Control  in  the  seventh 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE  69 

TABLE  32.  INFLUENCE  UPON  ERRORS  OF  VARIOUS  AMOUNTS 

OF  GUIDANCE  IN  THE  INITIAL  POSITION— ANIMAL  SUBJECTS 
A. 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

143.22 

16.93 

10.57 

4  (1-4) 

99-90 

60.25 

37.62 

6  (1-6) 

6973 

90.42 

56.46 

8  (1-8) 

71.53 

88.62 

55-34 

12  (1-12) 

8i.33 

78.82 

49.22 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

22.11 

— 1. 00 

—474 

4  (1-4) 

14.54 

—1.57 

— 12.10 

6  (1-6) 

10.87 

—2.05 

—23.24 

8  (1-8) 

5-84 

1.08 

15.67 

12  (1-12) 

3.28 

1-34 

29.00 

C. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

2.12 

—.14 

—7.07 

4  (1-4) 

1.46 

•85 

36.79 

6  (1-6) 

•43 

1.32 

75-43 

8  (1-8) 

•45 

1. 16 

72.05 

1 2  (1-12) 

.67 

.62 

48.06 

D. 


Group 

Av.  No.  of  Return 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(PerCent) 

2  (1-2) 

2.00 

—.88 

—85.98 

4  (i-4) 

1.03 

—.29 

—39.18 

6  (1-6) 

.60 

.28 

31-82 

8  (1-8) 

•30 

•43 

58.90 

12  (1-12) 

•74 

—.23 

—45.09 

70 


HELEN  LOIS  KOCH 


and  eighth  trials — trials  in  which  rapid  progress  is  being  made  in 
the  mastery  of  the  simple  cul-de-sac-less  maze — effects  a  decrease 
in  return  errors  which  is  sufficiently  great  to  counterbalance  the 
negative  effects  of  control  in  the  earlier  trials  and  to  produce,  as 
a  final  result,  an  actual  saving  in  the  average  number  of  return 
errors  amassed  per  directed  trial.  Guidance  from  the  eighth  to 
the  twelfth  trial  is,  likewise,  very  effective  in  reducing  the  return 
errors  made  per  controlled  run. 

The  subsequent  effect  of  control  (Table  32)  in  the  realm  of 
cul-de-sac  errors  is,  in  general,  to  produce  a  diminution  in  the 
number  amassed  per  trial.  Group  2  (1-2)  is  an  exception  to  this 
rule.  The  subsequent  effect  of  the  control  upon  cul-de-sac  errors 
becomes  beneficial  and  increasingly  so,  as  the  length  of  the  guided 
series  is  increased  to  six  trials,  but  the  relative  saving  decreases 
slightly  as  the  control  is  extended  to  eight  and  twelve  runs.  The 
same  general  relation  between  the  amount  of  control  and  the 
number  of  cul-de-sac  errors  made  per  trial  obtains,  if  we  consider 
merely  the  cul-de-sac  errors  made  by  each  of  the  groups  in  the 
trials  following  the  twelfth. 

A  deleterious  effect  on  the  part  of  the  control  upon  the  return 
errors  amassed  per  trial  in  the  post-control  period  is  apparent  in 
the  groups  guided  for  two,  four  and  twelve  trials;  six  and  eight 
directed  trials,  however,  reduce  the  retracings.  It  is  significant 
that,  in  each  of  the  five  cases,  the  relative  benefit  is  greater,  or  the 
relative  detriment  less,  in  the  realm  of  cul-de-sac  than  in  the  realm 
of  return  errors. 

The  probable  factors  determining  the  error  and  trial  scores 
just  described  have  been  frequently  indicated.  In  the  diffuse  re¬ 
action  characteristic  of  the  first  few  trials,  guidance  can  do  little 
to  establish  a  tendency  to  follow  the  true  pathway ;  yet  it  does  en¬ 
courage  the  formation  of  the  retracing  habit.  When  the  cul-de-sacs 
are  opened,  after  the  short  period  of  control,  the  animal  that 
has  a  tendency  to  retrace,  will  be  given  plenty  of  opportunities  to 
be  enticed  into  the  pitfalls.  The  unfavorable  effects,  then,  of  short 
series  of  directed  trials  introduced  at  the  beginning  of  the  learning 
process  may  be  greater  than  those  of  series  of  intermediate  lengths. 
The  retracing  habit,  when  the  controlled  series  of  trials  is  of  inter- 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


7 1 


mediate  length,  tends  to  decline  in  the  later  runs  of  the  period  of 
guidance,  and  proper  habits  are  established.  The  reaction,  more¬ 
over,  at  the  time  the  control  is  removed  is  sufficiently  plastic  to 
suffer  no  great  disruption  by  the  alteration  of  some  of  the  cues. 
The  longer  series,  on  the  other  hand,  permit  habits  of  consider¬ 
able  stability  to  develop.  Alteration  of  cues  is  more  likely  to  be 
disrupting  under  these  circumstances  than  in  the  less  extended 
series.  Hence  the  reason  for  the  relative  superiority  of  series  of 
medium  length  is  apparent. 


TABLE  33.  INFLUENCE  UPON  TIME  OF  VARIOUS  AMOUNTS  OF 

GUIDANCE  IN  THE  INITIAL  POSITION— ANIMAL  SUBJECTS 

A. 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

1389.86 

360.86 

20.61 

4  (1-4) 

1298.97 

451-75 

25-80 

6  (1-6) 

1079.61 

671. 11 

38.33 

8  (1-8) 

1076.73 

673.99 

38.50 

12  (1-12) 

1193.23 

55749 

32.99 

B. 


Group 

Av.  Time 
per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

367.82 

142.69 

27.95 

4  (i-4) 

234-87 

76.59 

24-59 

6  (1-6) 

174-59 

2.10 

1. 19 

8  (1-8) 

88.60 

16.57 

1576 

12  (1-12) 

5579 

53-82 

49.10 

C. 


Group 

Av.  Time  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

2  (1-2) 

3376 

— 11.72 

—53-66 

4  (i-4) 

30.99 

— 9.62 

—45.01 

6  (1-6) 

18.24 

1.78 

8.89 

8  (1-8) 

13.72 

5-03 

26.83 

12  (1-12) 

16.64 

i-39 

7.71 

72 


HELEN  LOIS  KOCH 


Influence  upon  time  (Table  33)  :  A  discussion  of  the  influence 
of  initial  guidance  upon  time  will  be  omitted,  since  the  time  scores 
exhibit,  in  general,  the  same  tendencies  revealed  in  the  error 
scores. 

2.  Influence  of  Various  Amounts  of  Guidance  Introduced 

Upon  the  Fifth  Trial 

The  discussion  of  this  section  must  be  limited  to  a  consideration 
of  the  effect  of  four  and  eight  guided  trials  upon  learning.  Since 
the  number  of  cases  in  each  group  is  small,  and  since  the  data  de¬ 
rived  under  only  two  different  conditions  are  being  compared,  no 
great  reliance  can  be  placed  on  the  results. 

TABLE  34.  INFLUENCE  UPON  TRIALS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  FIFTH  TRIAL- 

ANIMAL  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

4  (5-8) 

28.1 

57 

16.90 

8  (5-12) 

26.8 

7.0 

20.71 

Influence  {upon  trials  (Table  34)  :  Eight  directed  runs  intro¬ 
duced  upon  the  fifth  trial  are  slightly  more  effective  in  reducing 
the  number  of  trials  required  to  attain  a  mastery  of  the  maze, 
than  are  four  controlled  runs. 

Influence  upon  error  (Table  35)  :  From  the  point  of  view  of  the 
total  number  of  errors  amassed  during  the  learning,  four  and  eight 
guided  trials  are  equally  efficacious.  This  is  significant,  since  the 
greater  amount  of  control  does  result  in  a  slight  saving  in  trials. 
The  result  is  attributable  largely  to  the  immediate  effect  of  the 
guidance.  The  longer  period  of  control  accomplishes  an  increase 
in  the  number  of  return  errors  amassed  per  directed  run,  whereas 
the  shorter  does  not.  This  relation  is  an  anomaly  for  which  the 
writer  can  offer  no  explanation  except  that  of  chance.  One  would 
expect,  since  the  first  four  of  the  series  of  eight  controlled  trials 
exhibit  a  reduction  in  return  errors,  that  four  trials  more  of  prac¬ 
tice  under  unaltered  conditions  would  produce  a  relative  saving, 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


73 


TABLE  35.  INFLUENCE  UPON  ERRORS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  FIFTH  TRIAL- 

ANIMAL  SUBJECTS 
A. 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (5-8) 

107.71 

52.44 

32.74 

8  (5-12) 

107.71 

52.44 

32.74 

B. 


Av.  No.  of  Return 

Group 

Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (5-8) 

2.89 

.11 

3-67 

8  (5-12) 

2.43 

—.23 

—10.45 

C. 


Av.  No.  of  Cul-de-sac 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

4  (5-8) 

1. 01 

.60 

37.27 

8  (5-12) 

.70 

•59 

45-73 

D. 


Av.  No.  of  Return 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

4  (5-8) 

•57 

.16 

21.92 

8  (5-12) 

•50 

.01 

1.99 

at  least  equal  to  that  accomplished  in  the  first  four  trials,  if  not 
greater. 

The  scores  indicating  the  subsequent  effect  of  control  reveal  that 
the  longer  period  of  control  has  a  greater  beneficial  effect  upon 
cul-de-sac  errors  than  does  the  shorter,  and  that  the  reverse  is  true 
for  the  return  errors.  The  same  relation  between  the  error  scores 
of  the  two  groups  holds,  if  the  performance  in  the  trials  beyond 


74 


HELEN  LOIS  KOCH 


the  twelfth  is  considered.  Evidently,  then,  any  distraction  atten¬ 
dant  upon  the  alteration  of  cues  which  have  had  opportunity  in 
the  eight  guided  trials  to  become  well  integrated  into  the  reaction, 
manifests  itself  largely  in  the  realm  of  return  errors.  It  is,  also, 
probable  that  the  persistence  of  the  retracing  habit  established  dur¬ 
ing  the  period  of  control  is  responsible  for  the  small  saving  in 
return  errors  in  the  post-control  period  exhibited  by  group 
8  (5-12),  as  contrasted  with  the  saving  manifested  by  group 

4(5-8). 

TABLE  36.  INFLUENCE  UPON  TIME  OF  VARIOUS  AMOUNTS  OF 
GUIDANCE  INTRODUCED  UPON  THE  FIFTH  TRIAL- 

ANIMAL  SUBJECTS 
A. 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

4  (5-8) 

1547-30 

203.42 

11.61 

8  (5-12) 

1476.37 

274-35 

15-67 

B. 


Av.  Time 

Group 

per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (5-8) 

33-96 

13.87 

29.00 

8  (5-12) 

25-85 

6.46 

19.99 

C. 


A v.  Time  per  Trial 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

4  (5-8) 

18.45 

-30 

1.60 

8  (5-12) 

14.32 

3-7i 

20.58 

Influence  upon  time  (Table  36)  :  The  time  scores  indicate  little 
that  is  not  predictable  from  the  scores  in  trials  and  errors.  The 
saving  in  total  time  is  slightly  greater  when  more  guidance  is 
given  than  when  the  control  is  very  limited.  The  average  time  per 
directed  trial  is  less  than  the  normal,  but  group  4  (5-8),  contrary 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


75 


to  expectation,  exhibits  a  greater  relative  saving  than  does  group 
8  (5-12).  The  relative  saving  in  time  per  trial  for  the  trials  of  the 
post-control  period  is  greater  for  group  8  (5-12)  than  for  group 
4  (5-8).  Apparently  the  greater  distraction  attendant  upon  the 
removal  of  the  controlling  device  after  the  longer  period  of 
guidance  is  overbalanced  by  the  increased  facility  in  running  re¬ 
sulting  from  the  four  extra  directed  trials  given  group  8  (5-12), 
as  opposed  to  group  4  (5-8). 

B.  Results  Based  upon  the  Records  of  Human  Subjects 

1.  Influence  of  Various  Amounts  of  Initial  Guidance 

The  groups  of  subjects  whose  records  will  furnish  the  data  for 
the  discussion  of  this  section  were  guided  for  the  initial  2,  4,  6,  8 
or  12  trials. 


TABLE  37.  INFLUENCE  UPON  TRIALS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  IN  THE  INITIAL  POSITION- 
HUMAN  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H.2  (1-2) 

36.9 

74 

16.70 

H4  (1-4) 

37-1 

7.2 

16.26 

H6  (1-6) 

43-6 

•7 

1.58 

H8  (1-8) 

574 

— 13.1 

—36.09 

Hl2(l-I2) 

45-7 

—14 

—3.16 

Influence  upon  trials  (Table  37)  :  The  effect  upon  learning,  in  the 
case  of  the  human  subjects,  of  groups  of  controlled  trials  of  vari¬ 
ous  lengths,  when  the  period  of  guidance  has  not  been  preceded  by 
any  training,  diverges  greatly  from  that  noted  in  the  case  of  the 
animals.  The  efficacy  of  the  control,  from  the  point  of  view  of 
its  capacity  to  decrease  the  number  of  trials  required  by  the  hu¬ 
man  subjects  to  attain  a  mastery  of  the  maze,  varies,  generally 
speaking,  inversely  as  the  length  of  the  group  of  controlled  runs. 
Eight  and  twelve  directed  runs  even  effect  an  increase  above  the 
normal  in  the  number  of  trials  needed  for  learning  the  problem. 
Whether  the  greater  increase  in  trials  exhibited  by  group 


76 


HELEN  LOIS  KOCH 


H8  (1-8),  in  contrast  to  group  H12  (1-12),  is  a  fair  index  of 
what  would  happen,  were  a  much  larger  number  of  individuals 
considered,  is  a  question.  If  the  tendency  indicated  is  representa¬ 
tive,  then  we  may  say  that  the  efficacy  of  the  control  decreases  as 
the  control  is  increased  to  a  certain  amount.  If  more  guidance  is 
given,  however,  the  influence  of  control  becomes  less  detrimental. 
Such  a  condition  seems  not  at  all  improbable,  in  the  light  of  the 
general  tendencies  observed  in  the  error  scores. 

Influence  upon  errors  (Table  38)  :  The  influence  of  guidance  in 
the  initial  position  upon  the  total  number  of  errors  amassed  is  fa¬ 
vorable,  for  a  considerable  reduction  in  errors  is  exhibited  by 
each  of  the  five  groups  under  consideration.  Short  and  long  peri¬ 
ods  of  guidance  are  most  effective,  however.  It  is  significant  that 
this  result  is  diametrically  opposite  to  that  obtained  in  the  experi¬ 
ment  upon  animals.  The  reduction  in  the  total  number  of  errors 
made  by  the  groups  guided  for  the  longer  periods  is  apparently 
the  result  of  the  prevention  of  the  cul-de-sac  errors  by  the  con¬ 
trolling  device,  since  the  error  scores  for  the  post-control  period, 
as  well  as  the  return  error  scores,  for  the  period  of  guidance,  and 
the  trials  scores  are  all  higher  than  the  normal. 

The  immediate  influence  of  guidance  upon  return  errors  is 
favorable  when  the  period  of  control  is  short;  detrimental,  when 
it  is  longer.  In  general,  then,  the  efficacy  of  the  directed  runs  varies 
inversely  as  their  number.  Group  H8  (1-8)  is  slightly  aberrant. 
The  divergence  of  the  results  indicating  the  immediate  effect  of 
guidance  from  those  exhibited  in  the  animal  records  we  have 
already  attempted  to  explain  in  terms  of  the  barrier-like  function 
in  the  very  early  trials  of  the  turns  of  the  true  pathway,  with 
the  consequent  prevention,  to  a  large  degree,  of  retracings  of 
any  length.  As  soon  as  the  subject  is  slightly  familiar  with  the 
pathway,  his  behavior,  so  far  as  return  errors  are  concerned,  re¬ 
sembles  that  of  the  animals  in  the  first  few  trials. 

The  third  and  fourth  trials  are  less  effective  in  preventing  return 
errors  than  are  the  first  two.  In  the  fifth  and  sixth  guided  trials  the 
return  errors  are  greatly  increased  above  the  normal ;  in  the  sev¬ 
enth  and  eighth  trials,  they  are  again  much  reduced.  It  is  possible, 
perhaps  even  probable,  as  previously  suggested,  that  by  the  seventh 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


77 


TABLE  38.  INFLUENCE  UPON  ERRORS  OF  VARIOUS  AMOUNTS 

OF  GUIDANCE  IN  THE  INITIAL  POSITION— HUMAN  SUBJECTS 
A. 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

289.5 

104.2 

26.47 

H4  (1-4) 

255-0 

138.7 

35-23 

H6  (1-6) 

334-8 

58.9 

14.96 

H8  (1-8) 

326.4 

67.3 

17.09 

Hl2  ( I-I2) 

293-6 

100.1 

25.43 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

39-15 

17.20 

30.53 

H4  (1-4) 

33-55 

4-36 

11.50 

H6  (1-6) 

30.52 

—3-76 

—12.32 

H8  (1-8) 

19.76 

0.00 

0.00 

Hl2  ( I-I2) 

14.93 

—1.79 

—11.99 

C. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

2.19 

-.46 

—26.59 

H4  (1-4) 

1.38 

.16 

10.31 

H6  (1-6) 

1-75 

—.44 

— 33-59 

H8  (1-8) 

1.28 

—.07 

—5-79 

H12J1-12) 

1-37 

—•39 

— 39-8o 

D. 


Group 

Av.  No.  of  Return 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

3.39 

—.51 

— 17.71 

H4  (1-4) 

1.80 

.60 

25.00 

H6  (1-6) 

3-53 

— 1.68 

— 90.81 

H8  (1-8) 

1-57 

•03 

1.88 

Hl2  ( I-I2) 

2.03 

—.69 

—51-49 

78 


HELEN  LOIS  KOCH 


and  eighth  trials  in  a  series  of  guided  runs  the  subject  has  suf¬ 
ficiently  mastered  the  true  pathway  to  have  eliminated,  in  large 
measure,  the  retracing  habit.  At  any  rate,  the  saving  in  return 
errors  exhibited  in  the  seventh  and  eighth  trials  is  sufficient  to  bal¬ 
ance,  when  the  average  return  error  per  trial  for  the  first  eight 
trials  is  considered,  the  unfavorable  effect  of  the  fifth  and  sixth 
runs. 

Should  we  accept  the  explanation  just  offered  for  the  favorable 
influence  of  the  seventh  and  eighth  directed  trials,  we  have  the 
problem  of  the  unfavorable  influence  of  the  ninth  to  the  twelfth 
trials  to  consider.  This  we  have  suggested  may  be  the  result  of 
explorations  on  the  part  of  some  of  the  subjects  who,  as  soon  as 
they  feel  themselves  well  oriented,  set  up  as  their  next  problem  the 
detecting  of  some  more  obscure  or  hidden  short  route,  rather 
than  the  tedious  perfecting  of  a  well-nigh  perfect  habit.  The  re¬ 
marks  of  the  subjects  give  the  writer  some  faith  in  this  interpreta¬ 
tion  of  the  results. 

The  subsequent  effect  of  control  upon  the  average  number  of 
cul-de-sac  or  return  errors  amassed  per  trial  shows  no  consistent 
variation  with  the  length  of  the  period  of  guidance.  If,  however, 
we  consider  the  average  number  of  cul-de-sac  errors  made  per 
trial  by  each  of  the  groups  in  the  trials  after  the  sixteenth,  a  more 
consistent  variation  with  amount  of  control  is  apparent.  The  in¬ 
fluence  upon  the  cul-de-sac  errors  is,  in  each  case,  unfavorable; 
but  the  degree  of  unfavorableness  varies  directly  as  the  amount  of 
guidance.  The  return  error  scores  for  the  trials  subsequent  to  the 
sixteenth  show  no  such  regular  variation  with  the  amount  of  con¬ 
trol  administered. 

Influence  upon  time  (Table  39)  :  The  scores  indicating  the  total 
time  required  to  master  the  problem  manifest,  with  one  exception, 
small  savings  upon  the  normal.  They  exhibit,  however,  the  same 
general  pattern,  as  far  as  their  relation  to  amount  of  control  is 
concerned,  as  do  the  error  scores. 

The  immediate  effect  is  positive  and  greatest  for  the  shortest 
and  longest  control  periods.  The  large  saving  manifested  in  the 
trials  from  the  ninth  to  the  twelfth  is  significant,  because  in  these 
trials  we  have  an  increase  or,  at  least,  no  decrease  in  the  return 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE  79 

TABLE  39.  INFLUENCE  UPON  TIME  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  IN  THE  INITIAL  POSITION- 

HUMAN  SUBJECTS 

A. 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H 2  (1-2) 

I573-69 

3372 

2.10 

H4  (1-4) 

1548.63 

58.78 

3-66 

H6  (1-6) 

170575 

—98.34 

— 6.12 

H8  (1-8) 

1563.03 

44.38 

2.76 

Hl2  ( I-I2) 

1426.78 

180.63 

11.24 

B. 


Group 

Av.Time 

per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

I99.85 

50.40 

20.14 

H4  (1-4) 

149.92 

17.60 

10.50 

H6  (1-6) 

136.74 

— 21.12 

— 18.27 

H8  (1-8) 

74.58 

7.62 

9.27 

Hl2  ( I-I2) 

61.71 

12.97 

17-37 

C. 


Group 

Av.  Time  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (1-2) 

35.84 

— 11.04 

—44-52 

H4  (i-4) 

28.55 

—5-55 

—24.13 

H6  (1-6) 

27.27 

— 6.19 

—29.36 

H8  (1-8) 

17.98 

i-93 

9.69 

Hl2  ( I-I2) 

19-52 

— 1.60 

— 8.92 

errors.  Though  returns  may  be  increased,  time  is  saved  because 
of  the  prevention  of  cul-de-sac  errors. 

The  time  per  trial  in  the  post-control  period  is  increased,  gen¬ 
erally  speaking,  but  the  relative  increase  becomes  less  as  the  length 
of  the  guided  series  increases.  This  relation  between  time  and 
amount  of  guidance  may  be  a  direct  result  of  the  influence  of 
the  control  upon  the  time  or  it  may  be  a  result  of  the  increased 
number  of  trials  and  the  consequent  facility  in  traversing  the  maze 
acquired  with  increased  practice.  The  latter  hypothesis  seems  very 


8o 


HELEN  LOIS  KOCH 


reasonable  because  the  amount  of  loss  in  the  time  required  per 
trial  correlates  well  with  the  number  of  trials  taken  to  master  the 
maze. 

2.  Influence  of  Various  Amounts  of  Guidance 
Introduced  upon  the  Fifth  Trial 

Series  of  guided  trials  two  and  four  runs  in  length  were  intro¬ 
duced  upon  the  fifth  trial. 


TABLE  40.  INFLUENCE  UPON  TRIALS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  FIFTH  TRIAL- 

HUMAN  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H2  (5-6) 

43-o 

i-3 

2.93 

H4  (5-8) 

437 

.6 

1.36 

Influence  upon  trials  (Table  40)  :  Two  and  four  directed  runs 
interpolated  at  this  critical  intermediate  stage  of  the  learning  are 
scarcely  efficacious  in  reducing  the  number  of  trials  required  to 
master  the  maze.  Considering,  moreover,  the  variability  in  the 
trial  scores,  we  do  not  seem  justified  in  attempting  an  evaluation 
of  the  relative  effectiveness  of  the  two  series. 

Influence  upon  errors  (Table  41)  :  The  relative  efficacy  of  the 
two  series  of  guided  trials  is,  perhaps,  more  apparent  in  the  realm 
of  total  errors.  Control  extending  over  two  trials  increases  the 
total  number  of  errors  amassed  before  a  mastery  of  the  problem 
is  attained,  whereas  four  directed  trials  slightly  reduce  the  num¬ 
ber  of  errors. 

The  immediate  effect  of  the  guidance  upon  return  errors  is 
favorable  in  the  case  of  both  of  the  groups,  although  the  absolute, 
as  well  as  the  relative,  saving  is  greater  for  the  group  controlled 
for  only  two  trials.  This  relation  between  the  scores  of  the  two 
groups  is  scarcely  to  be  expected.  It  may,  however,  be  accounted 
for  in  much  the  same  way  as  the  similar  relation  between  the  scores 
of  the  groups  guided  for  the  initial  two  and  four  trials.  The 
turns  in  the  true  pathway  may  still  have  in  the  fifth  and  sixth, 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


81 


TABLE  41.  INFLUENCE  UPON  ERRORS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  FIFTH  TRIAL- 

HUMAN  SUBJECTS 
A. 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H 2  (5-6) 

427.6 

—33-9 

— 8.61 

H4  (5-8) 

378.5 

15-2 

3-86 

B. 


Av.  No.  of  Return 

Group 

Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (5-6) 

9.68 

1.94 

16.84. 

H4  (5-8) 

8.30 

.67 

747 

C. 


Av.  No.  of  Cul-de-sac 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

H2  (5-6) 

1.67 

—•36 

—27.48 

H4  (5-8) 

1.68 

—•47 

—38.84 

D. 


Av.  No.  of  Return 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

H2  (5-6) 

2.74 

-.89 

— 48.11 

H4  (5-8) 

1.84 

—.24 

—15.00 

as  a  result  of  the  uncertainty  produced  by  the  alteration  of  cues,  a 
sufficiently  barrier-like  action  to  prevent  long  retracings,  whereas 
in  the  seventh  and  eighth  runs  increasing  familiarity  with  the  true 
pathway  may  tend  to  favor  longer  returns  and,  consequently,  to 
produce  a  relatively  higher  error  score. 

The  effect  of  the  control  upon  the  number  of  errors  made  per 
trial  in  the  post-control  period  is  decidedly  deleterious.  The  short 


82 


HELEN  LOIS  KOCH 


series  of  directed  runs  has  a  more  unfavorable  effect  upon  return 
errors  than  upon  cul-de-sac  errors,  while  the  reverse  is  true  for 
the  group  guided  for  a  longer  time.  Since  in  the  case  of  the  human 
subjects,  four  trials  in  this  intermediate  position  is  a  sufficiently 
long  period  to  permit  the  subject  to'  develop  some  conscious  de¬ 
pendence  upon  the  cues  from  the  controlling  device,  and  since, 
moreover,  the  subject  is  not  informed  of  the  removal  of  the  con¬ 
trol,  one  might  expect  the  abstraction  of  the  guiding  cues  to  insti¬ 
gate  a  search  for  the  lost  cues  on  the  part  of  the  subject  and  hence 
increase,  to  a  relatively  greater  degree  than  would  the  two  directed 
trials,  the  number  of  cul-de-sac  errors  amassed  per  trial  in  the 
post-control  period.  The  result,  on  the  other  hand,  may  be  a  mere 
matter  of  chance. 

Influence  upon  time  (Table  42)  :  Since  the  time  scores  reveal 
nothing  significant,  they  will  not  be  discussed. 


TABLE  42.  INFLUENCE  UPON  TIME  OF  VARIOUS  AMOUNTS  OF 
GUIDANCE  INTRODUCED  UPON  THE  FIFTH  TRIAL— 


A. 

HUMAN  SUBJECTS 

Group 

Total  Time 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H2  (5-6) 

175948 

—152.07 

—946 

H4  (5-8) 

1597.22 

10.19 

•63 

B. 

Av.  Time 

Group 

per 

Absolute  Saving 

Relative  Saving 

Directed  Trial 

(Per  Cent) 

H2  (5-6) 

49.07 

2;92 

5.61 

H4  (5-8) 

42.17 

3.63 

7.09 

C. 

Ay.  Time  per  Trial 

Group 

for  Trials 

Absolute  Saving 

Relative  Saving 

Subsequent  to  Control 

(Per  Cent) 

H2  (5-6) 

27.79 

— 6.71 

—31.83 

H4  (5-8) 

22.90 

—2.99 

—15.02 

THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


83 


3.  Influence  of  Various  Amounts  of  Guidance 
Introduced  upon  the  Seventh  Trial 

The  influence  of  a  series  of  two  and  six  directed  trials  intro¬ 
duced  upon  the  seventh  run  will  furnish  the  material  for  the  dis¬ 
cussion  of  this  section. 

TABLE  43.  INFLUENCE  UPON  TRIALS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  SEVENTH  TRIAL — 

HUMAN  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H2  (7-8) 

41. 1 

3-2 

7.22 

H6  (7-12) 

37-1 

7.2 

16.24 

Influence  upon  trials  (Table  43)  :  Contrary  to  the  findings  up  to 
this  point,  the  longer  of  the  two  series  reduces  more  markedly 
than  the  shorter  the  number  of  trials  required  to  master  the  maze. 
Because  of  the  small  number  of  cases  in  each  group,  and  because 
of  our  failure  to  provide  a  series  of  groups  whose  periods  of 
guidance  shall  form  a  series  of  gradually  increasing  length,  the 
results  cannot  be  taken  too  seriously. 

Influence  upon  errors  (Table  44)  :  The  influence  of  two  and 
six  guided  runs  upon  the  total  error  scores  is  very  slight.  The 
two  series  of  directed  runs  are  about  equally  efficacious,  when 
efficacy  is  measured  in  terms  of  the  total  number  of  errors  made; 
but  the  manner  in  which  the  two  series  influence  errors  is  very  dif¬ 
ferent.  The  immediate  effect  of  the  two-trial  series  upon  return 
errors  is  decidedly  unfavorable,  whereas  that  of  the  six-trial  series 
is  markedly  favorable.  In  the  post-control  period,  on  the  other 
hand,  while  all  error  scores  are  increased  above  the  normal  in  both 
of  the  groups,  the  longer  series  of  controlled  runs  has  a  relatively 
more  unfavorable  effect  upon  cul-de-sac  errors  than  does  the  short 
series.  The  reverse  is  true  in  the  realm  of  return  errors. 


84  HELEN  LOIS  KOCH 

TABLE  44.  INFLUENCE  UPON  ERRORS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  SEVENTH  TRIAL- 

HUMAN  SUBJECTS 
A. 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H 2  (7-8) 

378.3 

154 

3-9i 

H6  (7-12) 

380.3 

134 

340 

B. 


Av.  No.  of  Return 

Group 

Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (7-8) 

8.72 

—1.94 

— 28.61 

H6  (7-12) 

3-95 

1-35 

25.61 

C. 


Av.  No.  of  Cul-de-sac 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

H2  (7-8) 

1.29 

—.08 

—6.61 

H6  (7-12) 

1. 16 

— .18 

-18.36 

D. 


Av.  No.  of  Return 
Errors  per  Trial 

Relative  Saving 

Group 

for  Trials 

Subsequent  to  Control 

Absolute  Saving 

(Per  Cent) 

H2  (7-8) 

2.06 

— .46 

—28.75 

H6  (7-12) 

1.45 

— .11 

— 8.21 

THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


85 


TABLE  45.  INFLUENCE  UPON  TIME  OF  VARIOUS  AMOUNTS  OF 
GUIDANCE  INTRODUCED  UPON  THE  SEVENTH  TRIAL- 

HUMAN  SUBJECTS 
A. 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 

(Per  Cent) 

H2  (7-8) 

1587-92 

19.49 

1 .21 

H 6  (7-12) 

1571.79 

35-62 

2.22 

B. 


Av.  Time 

Group 

per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (7-8) 

38.42 

2.52 

6.22 

H6  (7-12) 

25.90 

11.96 

31-59 

C. 


Av.  Time  per  Trial 

Group 

for  Trials 

Absolute  Saving 

Relative  Saving 

Subsequent  to  Control 

(Per  Cent) 

H2  (7-8) 

19.22 

.69 

3-46 

H6  (7-12) 

22.48 

—4-56 

—25-45 

Influence  upon  time  (Table  45)  :  The  influence  of  each  of  the 
two  series  of  directed  runs  upon  the  total  time  required  to  effect  a 
mastery  of  the  problem  is  practically  negligible.  This  result  is  the 
outcome,  however,  of  two  or  more  antagonistic  effects,  rather 
than  a  lack  of  influence  on  the  part  of  the  control.  The  immediate 
effect  of  the  longer  series  is  markedly  beneficial;  its  subsequent 
effect  is  decidedly  detrimental.  The  short  series,  on  the  other  hand, 
produces  a  slight  saving  in  the  time  consumed  per  trial  in  both  the 
control  and  post-control  periods.  The  increase  in  time  per  trial  for 
the  trials  of  the  post-control  period  exhibited  by  group  H6  (7-12) 
may  have  little  significance  as  an  index  of  the  influence  of  the 
control  upon  time,  for  this  group  displays  a  not  inconsiderable 
saving  in  trials.  Saving  in  trials,  as  we  have  so  often  indicated, 
operates  to  increase  the  time  per  trial  above  the  normal  through 
decreasing  the  practice  an  animal  gets  in  running  the  maze. 


86 


HELEN  LOIS  KOCH 


4.  Influence  of  Various  Amounts  of  Control 
Introduced  upon  the  Ninth  Trial 

The  experiment  was  so  arranged  that  series  of  two,  four  and 
eight  directed  trials  were  introduced  upon  the  ninth  run.  The 
group  guided  for  two  runs  we  have  referred  to  as  H2  (9-10)  ; 
that  guided  for  four  trials,  as  H4  (9-12) ;  and  the  group  con¬ 
trolled  for  eight  trials,  as  H8  (9-16). 


TABLE  46.  INFLUENCE  UPON  TRIALS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  NINTH  TRIAD- 

HUMAN  SUBJECTS 


Group 

Trials 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (9-10) 

35-6 

8.7 

19.04 

H4  (9-12) 

37-5 

6.8 

15.35 

H8  (9-16) 

37-1 

7.2 

16.36 

Influence  upon  trials  (Table  46)  :  Two,  four  and  eight  directed 
runs  all  operate  to  produce  a  reduction  in  the  number  of  trials 
required  to  master  the  problem.  No  direct  variation  of  the  amount 
of  benefit  with  the  amount  of  control  administered  is  apparent, 
however.  Very  little  control  seems  slightly  more  beneficial  than  a 
great  deal.  Control  in  medium  amounts  is,  on  the  other  hand,  less 
efficacious  than  more  generous  quantities. 

A  series  of  two  directed  trials  probably  operates  to  call  attention 
to  the  critical  elements  of  the  situation,  to  suggest  new  possibili¬ 
ties  without  disrupting,  to  any  degree,  the  old  procedure.  The 
four-trial  series  is,  doubtless,  sufficiently  extended  to  indicate 
vaguely  the  proper  method  of  procedure  to  the  subject,  and  not 
sufficiently  long  to  define  it  clearly.  Removal  of  the  control,  then, 
is  very  likely  to  be  disrupting  because  it  initiates  explorations 
aimed  at  the  recovery  of  cues  which  are  not  again  to  be  found. 
When  the  period  of  control  is  sufficiently  extended,  it  permits  the 
development  of  a  rather  clear  definition  of  the  situation  and  gives 
to  the  subject  confidence  in  his  conception  of  the  proper  path.  The 
removal  of  the  controlling  device  tends  to  be  recognized  as  an 
alteration  of  the  maze  pattern  which,  the  subject  infers,  has  been 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


8  7 


brought  about  by  the  experimenter.  Hence  he  is  not  very  much 
perturbed  by  the  modification. 

Influence  upon  errors  (Table  47)  :  The  hypothesis  just  ad¬ 
vanced  is  supported  by  both  the  error  and  time  scores.  Two  and 
eight  directed  runs  produce  a  saving  in  the  total  number  of  errors 
made;  four  controlled  trials,  on  the  other  hand,  are  detrimental, 
so  far  as  their  effect  upon  total  errors  is  concerned. 

The  number  of  return  errors  made  per  guided  trial  varies  in¬ 
versely  as  the  number  of  the  trials  in  the  series.  The  immediate 
influence  of  the  two'  and  four-trial  series  is  detrimental;  eight 
controlled  runs,  on  the  other  hand,  effect,  as  an  immediate  result, 
a  relatively  large  saving  in  return  errors. 

The  introduction  of  the  control  and  the  consequent  alteration 
of  the  cues  in  the  ninth  trial,  when  habits  have  become  well 
established,  is  confusing.  This  confusion  would  naturally  be  at 
its  maximum  in  the  first  two  trials  of  the  controlled  series.  By  the 
third  and  fourth  trials  of  the  guided  series  the  confusion  has,  to 
a  large  extent,  disappeared  and  the  total  number  of  return  errors 
made  is  reduced  below  the  normal,  but  not  sufficiently  to  counter¬ 
balance,  when  the  average  of  the  first  four  trials  is  taken,  the  in¬ 
crease  in  the  return  errors  apparent  in  the  first  two  trials.  The 
fifth  to  the  eighth  trials  of  the  guided  series  are  characterized  by 
a  marked  reduction  below  the  normal  of  the  return  errors  amassed 
per  trial.  This  condition  indicates  that  the  absence  of  cul-de-sacs, 
after  the  subject  becomes  adapted  to  the  altered  situation,  does  op¬ 
erate  to  decrease  the  number  of  return  errors  that  are  made. 

The  subsequent  effect  of  the  guided  series  upon  both  the  return 
and  cul-de-sac  errors  amassed  per  trial  in  all  three  of  the  groups 
is  unfavorable.  The  relative  increase  in  the  number  of  errors  made 
per  trial  in  the  post-control  period  is  least  in  the  case  of  the  group 
guided  for  two  runs  and  greatest  in  the  case  of  that  group  given 
four  directed  trials.  One  would  expect  that  the  more  fixed  the 
habit,  i.e.,  the  longer  the  period  of  control,  the  more  confusing 
the  removal  of  the  guiding  device  would  be,  but,  as  we  have  pre¬ 
viously  indicated,  there  is  a  possibility  of  emotional  and  idea¬ 
tional  factors  arising  to  favor  slightly  the  long  period  of  control 
as  opposed  to  that  of  intermediate  length. 


88 


HELEN  LOIS  KOCH 


TABLE  47.  INFLUENCE  UPON  ERRORS  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  NINTH  TRIAL- 

HUMAN  SUBJECTS 
A. 


Group 

Total  Errors 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (9-10) 

367.8 

25.9 

6.58 

H4  (9-12) 

417.6 

—230 

— 6.07 

H8  (9-16) 

362.7 

31.0 

7.87 

B. 


Group 

Av.  No.  of  Return 
Errors  per 
Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (9-10) 

9-57 

—5.82 

—155-20 

H4  (9-12) 

5.8i 

— 1.06 

— 22.23 

H8  (9-16) 

1.70 

1.81 

51.57 

C. 


Group 

Av.  No.  of  Cul-de-sac 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (9-10) 

1.36 

— .18 

—15.25 

H4  (9-12) 

1.63 

-65 

— 66.32 

H8  (9-16) 

1.03 

—.24 

—30.38 

D. 


Group 

Av.  No.  of  Return 
Errors  per  Trial 
for  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(PerCent) 

H2  (9-10) 

1-75 

—.41 

—30.59 

H4  (9-12) 

2.92 

—1.58 

— 117.91 

H8  (9-16) 

2.16 

—.86 

—66.15 

Influence  upon  time  (Table  48)  :  The  time  scores  reveal  few 
tendencies  that  are  not  apparent  in  the  error  scores.  Group 
H2  (9-10)  exhibits  a  considerably  greater  saving  in  the  total 
time  consumed  in  the  learning  of  the  maze,  as  contrasted  with 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


89 


TABLE  48.  INFLUENCE  UPON  TIME  OF  VARIOUS  AMOUNTS 
OF  GUIDANCE  INTRODUCED  UPON  THE  NINTH  TRIAL — 

HUMAN  SUBJECTS 
A. 


Group 

Total  Time 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (9-10) 

1389.19 

218.22 

13.57 

H4  (9-12) 

1566.48 

40.93 

2.57 

H8  (9-16) 

1554.15 

63.26 

3-94 

B. 


Group 

Av.  Time 

per 

Directed  Trial 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (9-10) 

41.07 

—9.42 

— 29.76 

H4  (9-12) 

32.73 

346 

9-57 

H8  (9-16) 

24.31 

5-68 

18.94 

C. 


Group 

Av.  Time  per  Trial 
For  Trials 

Subsequent  to  Control 

Absolute  Saving 

Relative  Saving 
(Per  Cent) 

H2  (9-10) 

20.43 

—1.63 

—8.67 

H4  (9-12) 

21.77 

—3.85 

— 21.48 

H8  (9-16) 

21.21 

—4-52 

— 27.08 

groups  H4  (9-12)  and  H8  (9-16),  than  the  error  scores  would 
lead  one  to  suspect.  The  relative  increase,  furthermore,  in  the 
time  required  per  trial  in  the  post-control  period  varies  directly  as 
the  amount  of  guidance  granted.  This  tendency  is  also  somewhat 
surprising  in  view  of  the  error  scores.  The  results  are  not  out  of 
keeping,  however,  with  the  hypothesis  set  forth  in  the  previous 
paragraph.  One  would  expect  the  individual  who  rather  clearly 
recognizes  the  alteration  of  the  maze  when  the  controlling  device 
is  removed  and  believes,  perhaps,  that  he  is  being  tricked,  to  be 
slow  and  deliberate  in  his  movements. 


90 


HELEN  LOIS  KOCH 


SUMMARY 

A.  Results  of  Experimentation  upon  Animals : 

1.  The  efficacy  of  control  is  a  function  of  the  amount  admin¬ 
istered. 

2.  When  guidance  is  given  in  the  early  trials,  its  efficacy  in¬ 
creases  as  the  number  of  directed  runs  is  increased  up  to  a  certain 
optimum  number.  If  the  length  of  the  guided  series  is  further  ex¬ 
tended,  the  efficacy  of  the  control  decreases.  This  tendency  is 
manifested  in  the  scores  indicating  the  trials  required,  the  total 
errors  made,  and  the  total  time  consumed,  as  well  as  the  errors 
made  per  trial  and  time  required  per  trial  in  the  post-control 
period. 

The  optimum  amount  of  guidance  is  probably  that  which  per¬ 
mits  a  fairly  clearly  defined  habit  to  develop,  but  terminates  when 
the  habit  is  still  sufficiently  plastic  to  allow  a  ready  substitution  of 
new  cues  as  stimuli  for  the  proper  responses, 

3.  In  the  early  trials  of  a  controlled  series  the  immediate  influ¬ 
ence  of  guidance  upon  the  number  of  return  errors  made  per  trial 
is  unfavorable.  In  the  later  trials  of  the  series,  however,  the  pre¬ 
vention  of  cul-de-sacs  operates  to  reduce  far  below  the  normal  the 
number  of  retracings. 

The  probable  explanation  for  this  fact  has  been  indicated  in  the 
body  of  the  present  chapter,  as  well  as  in  the  summary  of  the  pre¬ 
ceding. 

4.  Of  four  and  eight  directed  trials  interpolated  upon  the  fifth 
run,  eight  trials  are,  in  general,  the  more  efficacious.  The  imme¬ 
diate  effect  of  the  four-trial  series  upon  the  time  consumed  per 
trial,  and  the  immediate,  as  well  as  subsequent,  effect  of  the  same 
series  upon  the  number  of  return  errors  amassed  per  trial,  is, 
however,  more  favorable  than  that  of  the  eight-trial  series.  No 
great  reliance,  however,  can  be  placed  upon  these  results. 

B.  Results  of  Experimentation  upon  Human  Subjects: 

1.  The  efficacy  of  control  varies  with  the  amount  administered. 

2.  The  relative  effectiveness  of  various  amounts  of  guidance  is 
a  function  of  the  position  in  the  learning  process  at  which  the 
control  is  interpolated. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


9i 


3.  Ill  the  early  and  late  stages  of  the  learning,  the  very  short 
or  very  long  periods  of  the  control  are  more  efficacious  than  the 
periods  of  medium  length.  This  relation  is  apparent  when  efficacy 
is  measured  in  terms  of  the  number  of  trials  required  or  the  total 
errors  made  or  the  total  time  consumed.  The  control  period  must 
either  be  so  short  that  it  merely  calls  attention  in  a  vague  way  to 
the  critical  elements  of  the  situation  without  markedly  disrupting 
the  old  procedure,  or  so  long  that  it  permits  the  development  of  a 
rather  clear  conception  of  the  true  pathway  and  an  attendant  con¬ 
fidence. 

4.  Upon  the  relative  efficacy  of  various  amounts  of  control  in¬ 
terpolated  in  an  intermediate  position  in  the  sequence  of  trials, 
no  generalization  can  be  made. 

5.  When  guidance  is  given  in  the  early  stages  of  the  learn¬ 
ing,  its  immediate  effect  upon  return  errors  is  favorable,  if  the 
period  of  control  is  short;  unfavorable,  if  the  period  of  control  is 
long.  The  reverse  is  true,  when  the  series  of  controlled  trials  is 
interpolated  later  in  the  learning. 

The  probable  explanation  of  the  relation  between  the  number 
of  return  errors  made  per  directed  trial  to  the  length  of  the  period 
of  control,  when  the  guidance  is  given  in  the  early  stages  of  the 
learning,  has  been  indicated  in  the  summary  of  the  preceding 
chapter. 

When  the  directed  trials  are  interpolated  later  in  the  learning, 
the  alteration  of  cues  attendant  upon  the  introduction  of  the  con¬ 
trolling  device  causes  confusion  and  much  retracing.  This  confu¬ 
sion  is  easily  overcome  if  the  period  of  control  is  extended;  and 
then  the  absence  of  cul-de-sacs  favors  a  rapid  mastery  of  the 
simple  pathway  with  a  consequent  marked  reduction  in  the  return 
errors. 

6.  No  generalization  can  be  made  concerning  the  relative  sub¬ 
sequent  effect  upon  errors  of  various  amounts  of  control. 

7.  When  the  guidance  occurs  at  any  but  the  earliest  period  of 
the  learning,  the  saving  in  time  per  directed  trial  varies  directly 
with  the  amount  of  control  given.  The  reverse  relation  holds  be¬ 
tween  the  time  consumed  per  trial  in  the  post-control  period  and 
the  amount  of  guidance. 


9  2 


HELEN  LOIS  KOCH 


8.  In  the  case  of  guided  series  occurring  very  early  in  the  trial 
sequence,  the  immediate  effect  of  little  or  much  control  upon  the 
average  time  required  per  trial  is  favorable;  that  of  a  medium 
amount,  unfavorable.  The  subsequent  effect  upon  the  time  re¬ 
quired  per  trial  of  various  amounts  of  control  in  the  initial  posi¬ 
tion  is,  generally  speaking,  deleterious.  The  degree  to-  which  the 
time  per  trial  is  increased  above  the  normal  varies  inversely  with 
the  amount  of  control.  This  latter  relation  may  be  an  indirect  re¬ 
sult  of  the  influence  of  control  upon  trials,  rather  than  the  direct 
outcome  of  its  action  upon  time.  In  the  degree  ff>  which  control 
reduces  the  number  of  trials  required,  it  decreases  the  length  of 
the  practice  period,  and  hence,  perhaps,  the  general  facility  with 
which  the  problem  is  handled. 

9.  The  results  obtained  in  the  experiment  upon  human  and 
animal  subjects  are  in  most  respects  opposite.  The  divergence 
may  be  a  consequence  of  the  species  difference,  a  difference  in 
the  distribution  of  the  effort,  or  some  other  unavoidable  varia¬ 
tion  in  the  procedure  of  the  two  experiments.  The  reason  for  the 
difference  needs  further  investigation. 


IV 

THE  INFLUENCE  OF  CONTROL  UPON  RETENTION 


It  has  been  a  popular  belief  that  responses  developed  by  one’s 
own  unaided  efforts  are  more  thoroughly  integrated  into  his  action 
systems  than  those  developed  under  guidance ;  that  what  one  learns 
without  aid,  he  retains  best.  The  doctrine  has  accumulated  con¬ 
siderable  weight  because  of  its  relation  to  certain  moral  principles, 
as  well  as  because  of  the  absence  of  any  definite  contradictory 
evidence.  No  experimental  studies  which  would  cast  light  upon 
the  validity  of  the  belief  have  been  reported.  Hence  our  investiga¬ 
tion  of  the  problem,  though  neither  elaborate  nor  extensive,  should 
have  at  least  suggestive  value. 

Our  inquiry  was  limited  merely  to  a  consideration  of  the  influ¬ 
ence  of  guidance  upon  the  retention  of  a  motor  habit  by  human 
subjects.  Retention,  moreover,  was  measured  in  terms  of  the 
number  of  errors  made  and  the  time  consumed  in  a  single  tracing 
of  the  maze  forty-eight  hours  after  the  problem  had  been  mas¬ 
tered.  No  attempt  was  made  to  trace  the  influence  of  guidance  up¬ 
on  the  course  of  the  disintegration  of  the  habit. 

The  results  (see  Tables  49  and  50)  of  our  investigation  indicate 
that  guidance  does  influence  the  retention  of  a  motor  habit.  Under 
certain  conditions  the  effect  of  control  is  favorable ;  under  others, 
detrimental.  The  efficacy  of  the  directed  runs  is  determined,  in 
part  at  least,  by  the  number  employed  and  the  position  at  which 
they  are  interpolated  in  the  learning  period.  It  is  evident  from 
Table  49  that  the  accuracy  with  which  the  habit  functions  after  a 
lapse  of  forty-eight  hours  varies,  generally  speaking,  inversely  as 
the  distance  of  the  period  of  guidance  from  the  beginning  of  the 
learning.  Control  interpolated  in  the  early  stages  of  the  learning 
period  tends  to  decrease  below  the  normal  the  number  of  errors 
made  in  the  retention  test,  whereas  guidance  given  in  the  trials 
subsequent  to  the  sixth  is  unfavorable  in  its  influence  upon  error. 
No  very  consistent  relation,  on  the  other  hand,  is  apparent  be- 


93 


94 


HELEN  LOIS  KOCH 


tween  the  time  consumed  in  the  test  for  retention  and  the  position 
in  the  learning  at  which  the  guided  effort  occurs, 

TABLE  49.  TOTAL  NUMBER  OF  ERRORS  MADE  IN  THE 

RETENTION  TEST 


No.  of  Directed 
Trials  in  the 
Learning  Period 

Trial  upon  Which  the  Controlled  Series  is  Introduced 

1 

3 

5 

7 

9 

11 

2 

1.0 

2.7 

2.4 

4-3 

5-i 

4.8 

4 

2.1 

2.8 

,8 

6 

2.4 

9.1 

8 

1.4 

4-6 

12 

3-i 

Error  Score 

of 

3-5 

3-5 

3-5 

3-5 

3-5 

3-5 

Normal  Group 

TABLE  50.  TOTAL  TIME  CONSUMED  IN  THE  RETENTION  TEST 


No.  of  Directed 
Trials  in  the 
Learning  Period 

Trial  upon  Which  the  Controlled  Series  is  Introduced 

1 

3 

5 

7 

9 

11 

2 

28.0 

21.0 

19.9 

21.9 

31-4 

22.0 

4 

24.4 

17.6 

18.8 

6 

19.7 

27.7 

8 

21.0 

3 1. 1 

12 

18.6 

Time  Score 

of 

26.1 

26.1 

26.1 

26.1 

26.1 

26.1 

Normal  Group 

Among  the  groups  in  which  the  period  of  controlled  learning 
began  before  the  ninth  trial,  the  number  of  errors  accumulated  in 
the  test  for  retention  tends  to  vary  directly  as  the  amount  of 
guidance  administered.  The  time  consumed  in  the  retention  test 
by  the  groups  which  were  guided  early  in  the  learning  period  tends 
to  vary,  on  the  contrary,  inversely  as  the  number  of  directed  trials. 

The  relation  between  the  effect  of  guidance  upon  learning  and 
its  effect  upon  retention  is  suggested  by  the  correlations  in  Tables 
51  and  52.  The  influence  of  two  guided  trials  upon  the  number  of 
errors  accumulated  in  the  learning  period  tends,  in  a  general  way, 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


95 


TABLE  si.  CORRELATIONS  BETWEEN  THE  RANK  OF  INDIVIDU¬ 
ALS  IN  TERMS  OF  ERRORS  MADE  IN  THE  LEARNING 
WITH  THE  RANK  IN  TERMS  OF  ERRORS  MADE  IN  THE 
RETENTION  TEST1 


No.  of  Guided 
Trials  in  the 
Learning  Period 

Trial  upon  Which  the  Guided  Series  is  Introduced 

i 

3 

5 

7 

9 

11 

2 

—•37 

—.14 

+-3i 

—•39 

—•50 

— .01 

4 

+40 

+•25 

+48 

6 

+.69 

+.66 

8 

+-71 

— .21 

12 

+.60 

Correlation  in 

Case  of 

+.15 

Normal  Group 

1  All  correlations  reported  in  this  monograph  are  based  upon  Spearman’s 
formula : 

6  2  D2 

P  =  1 - 

N  (N2  —  i) 


to  be  the  reverse  of  its  influence  upon  the  number  of  errors  made 
in  the  retention  test.  The  correlation  between  the  quantities  just 
indicated  are  negative  and,  though  small,  are  rather  consistently 
larger  than  the  correlation  between  the  same  quantities  in  the  nor¬ 
mal  group.  In  the  case  of  the  groups  controlled  for  a  period  ex¬ 
tending  over  more  than  two  trials,  the  correlation  between  the 
number  of  errors  made  in  the  learning  period  and  that  made  in 
the  retention  test  is,  as  a  rule,  positive.  As  the  amount  of  initial 
guidance  is  increased,  the  size  of  the  correlation  between  the  quan¬ 
tities  in  question  increases. 

In  the  case  of  the  groups  guided  at  an  early  stage  of  the  learn¬ 
ing  the  correlation  between  the  time  required  for  attaining  a 
mastery  of  the  problem  and  the  time  consumed  in  the  retention 
test  is  positive  and  decreases  in  size  as  the  length  of  the  period  of 
control  is  extended.  Control,  on  the  other  hand,  introduced  upon 
the  ninth  trial  or  beyond,  produces  a  negative  correlation  between 
the  learning  time  and  the  time  required  in  the  retention  test.  Guid¬ 
ance  in  an  intermediate  position  and  not  too  limited  in  amount 
gives  rise  to  a  positive  correlation  between  the  two  quantities  un¬ 
der  discussion. 


96  HELEN  LOIS  KOCH 

TABLE  52.  CORRELATION  BETWEEN  THE  RANK  OF  INDIVIDU¬ 
ALS  IN  TERMS  OF  THE  TIME  CONSUMED  IN  THE  LEARN¬ 
ING  PERIOD  WITH  THE  RANK  IN  TERMS  OF  THE  TIME 
REQUIRED  IN  THE  RETENTION  TEST 


No.  of  Directed 
Trials  in  the 
Learning  Period 

Trial  upon  Which  the  Guided  Series  is  Introduced 

1 

3 

5 

7 

9 

11 

2 

+•59 

-.58 

+•58 

— 40 

—.29 

—•23 

4 

+.22 

+•32 

—•36 

6 

+•56 

+.76 

8 

+.48 

—•23 

12 

+•25 

Correlation  in 

Case  of 

+.13 

Normal  Group 

The  correlation  between  the  trial  scores  of  the  various  groups 
and  the  error  or  time  scores  in  the  retention  test  do  not  deviate 
sufficiently  from  the  normal  nor  exhibit  sufficient  regularity  to 
justify  any  generalizations. 

The  mechanism  by  which  control  influences  the  retention  of  the 
maze  habit  is  not  entirely  obvious.  Several  possible  hypotheses  in 
regard  to  this  mechanism  suggest  themselves ;  but  they  are  largely 
a  priori  in  character  and  are  offered  only  for  what  they  are  worth. 
In  so  far  as  the  control  prevents  the  formation  of  false  habits, 
it  should  react  favorably  upon  retention,  for  as  the  maze  habit  dis¬ 
integrates  and  the  organized  proper  response  is  no  longer  power¬ 
fully  dominant,  it  is  less  probable  that  false  reactions  will  occur  in 
the  test  for  retention,  if  they  have  never  been  experienced,  than  if 
the  subject  has  frequently  indulged  in  them.  This  error-preventing 
capacity  of  the  control  is  greatest  when  the  period  of  guidance 
occurs  in  the  early  stage  of  the  learning,  because  it  is  in  this  stage 
that  elaborate  explorations  prevail.  Hence,  one  would  expect  guid¬ 
ance  in  the  early  trials  to  act  most  favorably  upon  retention.  This 
our  results  indicate  to  be  the  case. 

The  hypothesis  just  advanced  may,  furthermore,  account  in 
part  for  the  rather  consistently  positive  correlations  between  the 
error  scores  for  the  learning  period  of  the  groups  given  initial 
guidance,  and  their  error  scores  in  the  retention  tests. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


97 


Control  not  only  operates  to  prevent  the  formation  of  some 
improper  habits,  but  it  may  establish  a  dependence  upon  false 
cues.  To  the  extent  to  which  guidance  does  result  in  the  formation 
of  two  modes  of  response  to  many  elements  of  the  maze  situation, 
and  to  the  extent  that  these  are  conflicting,  in  part,  at  least,  it  is 
probable  that  control  may  have  a  deleterious  action.  If  the  habit 
has  disintegrated  far  enough  to  weaken  or  destroy  the  dominance 
of  the  organized  response  not  dependent  upon  the  controlling  de¬ 
vice  for  cues,  or  the  dominance  of  a  concept  of  the  relations  of  the 
various  parts  of  the  maze,  a  conflict  of  tendencies  may  result  with 
a  consequent  increase  in  the  error  score  of  the  retention  test. 
Such  a  mode  of  functioning  on  the  part  of  the  control  may  ac¬ 
count  for  the  direct  relation  between  the  number  of  errors  accu¬ 
mulated  in  the  test  for  retention  and  the  amount  of  guidance  given 
in  the  learning  period,  as  well  as  the  detrimental  effect  upon  re¬ 
tention  of  the  directed  runs  introduced  in  the  later  stages  of  the 
learning. 

The  favorable  influence  of  the  longer  period  of  control  upon 
the  time  consumed  in  the  retention  test  may  be  the  result  of  a  gen¬ 
eral  speed  set  determined  early  in  the  period  in  which  the  habit  is 
being  acquired,  by  the  simplicity  of  the  task  of  mastering  the  cul- 
de-sac-less  maze  and  the  consequent  confidence  in  ability  to  suc¬ 
ceed. 


V 

THE  INFLUENCE  OF  GUIDED  LEARNING  UPON  THE 
ADAPTABILITY  OF  THE  LEARNED  REACTION 

The  adaptability  of  the  reaction  established  with  the  aid  of 
guidance  was  tested  by  having  each  subject  trace  the  maze  under 
a  series  of  nine  distracting  conditions,  forty-eight  hours  after  he 
had  mastered  the  problem.  The  distractions  employed  were :  a 
shifting  of  the  position  of  the  maze  through  90,  180  and  270  de¬ 
grees,  respectively;  the  silent  recitation  of  the  first  stanza  of 
“Mary  had  a  little  lamb”;  reading  aloud  from  a  scientific  text; 
drawing  triangles  with  the  left  hand;  tracing  the  maze  with  the 
left  hand;  traversing  it  from  goal  to  entrance;  and  lastly,  while 
tracing  the  maze  with  the  left  hand,  drawing  triangles  with  the 
right.  The  distractions  were  given  in  the  indicated  order.  One  trial 
only  under  each  of  the  conditions  was  allowed.  In  those  tests  char¬ 
acterized  by  a  modification  in  the  position  of  the  maze,  the  sub¬ 
ject  had  no  knowledge  of  the  alteration. 

The  results  of  these  tests  are  given  in  Tables  53  to  61.  Both 
error  and  time  records  were  taken,  but  since  both  exhibit  the  same 
tendencies,  only  the  results  based  upon  the  error  records  are  pre¬ 
sented  in  the  tables. 

An  inspection  of  the  data  reveals  the  fact  that  guidance  some¬ 
times  increases  and  sometimes  decreases  the  adaptability  of  the 
maze  habit.  The  nature  and  degree  of  the  influence  of  control  is 
apparently  a  function  of  three  interrelated  conditions  : 

( 1 )  Amount  of  guidance  :  In  the  test,  for  example,  in  which  the 
maze  is  traversed  with  the  right  hand  while  the  left  is  engaged  in 
drawing  triangles,  the  effect  of  initial  guidance  is  invariably  dele¬ 
terious  and  the  degree  of  detriment  varies  directly  with  the 
amount  of  control  given. 

As  the  period  of  guidance  introduced  upon  the  ninth  run  is  ex¬ 
tended  from  two  to  eight  trials,  the  effect  upon  the  adaptability  of 


98 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


99 


the  learned  reaction  to  the  180  degree  shift  in  the  position  of  the 
maze  becomes  increasingly  unfavorable. 

Various  amounts  of  initial  guidance  have  a  similar  influence 
upon  the  adaptability  of  the  reaction  to  the  conditions  of  the  tests 
in  which  the  maze  is  traversed  while  the  subject  silently  recites  a 
jingle,  or  while  he  reads  aloud,  as  well  as  that  in  which  the  posi¬ 
tion  of  the  maze  is  shifted  90  degrees.  The  effect  of  the  initial  two 
trials  is  somewhat  deleterious;  four  trials  are  distinctly  favorable; 
while  as  the  number  of  guided  trials  is  extended  from  four  to 
twelve,  the  influence  becomes  increasingly  less  favorable  or  more 
unfavorable. 

These  illustrations  serve  merely  to  demonstrate  that  the  adapta¬ 
bility  of  the  maze  reaction  to  altered  conditions  is  a  function  of  the 
amount  of  guidance  given  in  the  learning  period.  The  particular 
relations  that  obtain,  however,  between  the  amount  of  control  and 
its  effect  upon  the  adaptability  of  the  habit  is  conditioned  by  the 
position  in  the  learning  at  which  the  given  amount  is  interpolated, 
as  well  as  the  situation  to  which  the  habit  must  be  adjusted.  Four 
guided  trials,  for  example,  in  the  initial  position  increase  above 
the  normal  the  errors  made  in  the  test  in  which  the  maze  is  shifted 
180  degrees,  whereas  they  act  to  reduce  the  number  of  errors  ac¬ 
cumulated  in  the  test  characterized  by  silent  recitation  or  reading 
aloud. 

(2)  Position  of  guidance:  The  adaptability  of  the  reaction  in 
the  case  of  the  groups  controlled  for  four  trials  varies  inversely, 
in  seven  of  the  tests,  as  the  distance  of  the  period  of  guidance  from 
the  initial  trial.  Under  most  of  the  other  conditions  presented  by 
the  tests,  the  influence  of  the  position  of  the  guided  learning  is 
less  regular  in  its  manifestations. 

(3)  Nature  of  the  problem :  There  are  some  problems  to  which 
the  reaction  mastered  with  the  aid  of  guidance  is  almost  invariably 
adapted  with  more  difficulty  than  that  learned  without  guidance ; 
other  problems  in  which  the  reverse  is  true.  The  test  in  which  the 
maze  is  traversed  from  the  goal  back  to  the  entrance,  as  well  as 
that  in  which  one  hand  draws  triangles  while  the  other  traces  the 
maze,  are  examples  of  the  former  type.  The  test  characterized  by 
silent  recitation  or  guiding  the  stylus  with  the  left  hand  are  exam- 


100 


HELEN  LOIS  KOCH 


pies  of  the  latter  type.  The  general  characteristics  of  the  two  types 
of  problem  are  not  apparent.  In  fact,  any  functional  classification 
of  the  problems  that  can  be  made  must  be  so  elastic  it  loses  all 
significance. 

It  has,  doubtless,  occurred  to  the  reader  that  probably  some  of 
the  problems  do  not  test  the  adaptability  of  the  reaction  at  all,  but 
rather  the  stability  of  the  habit  under  distraction.  The  tasks  which 
one  would  set  apart  on  a  priori  grounds  as  tests  of  the  stability  of 
the  habit  are  those  in  which  the  subject  traverses  the  maze  while 
silently  reciting  a  jingle,  while  reading  aloud,  or  while  his  left 
hand  is  engaged  in  drawing  triangles.  If  these  problems  actually 
test  the  stability  of  the  reaction,  one  would  be  justified  in  expect¬ 
ing  guidance  to  influence  the  performance  of  the  tasks  in  a  man¬ 
ner  similar  to  that  in  which  it  influenced  performance  in  the  re¬ 
tention  test.  The  results  of  these  three  tests  do  not,  however,  ex¬ 
hibit  any  higher  or  more  consistent  correlations  with  the  results  of 
the  retention  test  than  are  manifested  by  some  of  the  other  more 
distinctly  adaptive  problems.  The  correlation,  furthermore,  of 
the  results  of  the  three  tests  with  the  results  in  the  learning  period 
do  not  vary  in  the  same  way  with  the  manner  in  which  guidance 
is  employed,  as  do  the  correlations  between  the  results  of  the  learn¬ 
ing  and  retention  tests.  Hence,  a  classification  of  the  problems  on 
the  basis  of  the  degree  to  which  they  test  stability  or  adaptability 
seems  unwarranted. 

The  great  complexity  of  the  conditions  resulting  from  the  inter¬ 
action  of  the  three  dependent  variables — the  nature  of  the  prob¬ 
lem,  the  amount  of  guidance  and  its  position — renders  impossible, 
at  present,  the  prediction  of  the  effect  of  any  single  factor,  as  well 
as  any  intelligent  explanation  of  the  results. 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


IOI 


TABLE  53.  SCORES  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  A  ROTATION 
OF  THE  POSITION  OF  THE  MAZE  THROUGH  90  DEGREES 


No.  of  Directed 

Trials  in  the 
Learning  Period 

Trial  upon  Which  the  Controlled  Series  is  Introduced 

1 

3 

5 

7 

9 

11 

2 

28.1 

51.8 

93-9 

94-7 

36.1 

59-3 

4 

13.2 

4i.3 

47-3 

6 

19.7 

43-0 

8 

28.0 

26.5 

12 

847 

Error  Score 
of 

Normal  Group 

22.9 

22.9 

22.9 

22.9 

22.9 

22.9 

TABLE  54.  SCORES  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  A  ROTATION 
OF  THE  POSITION  OF  THE  MAZE  THROUGH  180  DEGREES 


No.  of  Directed 
Trials  in  the 
Learning  Period 

Trial  upon  Which  the  Guided  Series  is  Introduced 

1 

3 

5 

7 

9 

11 

2 

32.8 

16.2 

11. 1 

15-5 

20.5 

27.8 

4 

II-3 

150 

254 

6 

19.5 

7-5 

8 

12.8 

30.0 

12 

136.6 

Error  Score 

of 

18.0 

18.0 

18.0 

18.0 

18.0 

18.0 

Normal  Group 

102 


HELEN  LOIS  KOCH 


TABLE  55.  SCORES  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  A  ROTATION 
OF  THE  POSITION  OF  THE  MAZE  THROUGH  270  DEGREES 


No.  of  Directed 
Trials  in  the 
Learning  Period 

Trial  upon  Which  the  Guided  Series  is  Introduced 

1 

3 

5 

7 

9 

11 

2 

14.0 

21.9 

35-9 

19-9 

4.2 

5.9 

4 

12.8 

18.9 

96.4 

6 

73 

15-4 

8 

10.9 

18. 1 

12 

44-8 

Error  Score 

• 

of 

12.8 

12.8 

12.8 

12.8 

12.8 

12.8 

Normal  Group 

TABLE  56.  SCORES  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  SILENT  RECI¬ 
TATION 


No.  of  Directed 
Trials  in  the 
Learning  Period 

Trial  upon  Which  .the  Guided  Series  is  Introduced 

1 

3 

5 

7 

9 

11 

2 

7-5 

1.6 

1.8 

7-1 

1.2 

1.6 

4 

2.2 

7.2 

384 

6 

3-2 

2.3 

8 

5-7 

8.1 

12 

344 

Error  Score 

of 

39 

3-9 

3-9 

3-9 

39 

3-9 

Normal  Group 

THE  INFLUENCE  OF  MECHANICAL  GUIDANCE  103 

TABLE  57.  SCORES  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  READING 
ALOUD 


No.  of  Directed 

Trials  in  the 
Learning  Period 

Trial 

upon  Which  the  Guided  Series  is  Introduced 

1 

3 

5 

7 

9 

II 

2 

97 

5-4 

1.9 

37 

6.4 

47 

4 

1.0 

8.8 

1 1.6 

6 

5.1 

9-8 

8 

9.8 

1.2 

12 

13-3 

Error  Score 

of 

1.9 

1-9 

1.9 

1.9 

1.9 

1.9 

Normal  Group 

TABLE  58.  SCORES  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  TRAVERSING 
THE  MAZE  FROM  THE  GOAL  BACK  TO  THE  BEGINNING 


No.  of  Directed 

T rials  in  the 

Trial  upon  Which  the  Guided  Series  is  Introduced 

Learning  Period 

1 

3 

5 

7 

9 

11 

2 

4 

6 

8 

12 

12.6 

15.1 
12.0 
10.3 

10.2 

11 7 

8.6 

54-8 

10.0 

4-4 

20.7 

70.0 

11. 1 

79 

Error  Score 

of 

Normal  Group 

7-1 

7-1 

7-1 

7-1 

7-1 

7.1 

104 


HELEN  LOIS  KOCH 


TABLE  59.  SCORES  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  THE  TRAVERS¬ 
ING  OF  THE  MAZE  WITH  THE  LEFT  HAND 


No.  of  Directed 
Trials  in  the 

Trial  upon  Which  the  Guided  Series  is  Introduced 

Learning  Period 

i 

3 

5 

7 

9 

11 

2 

7-8 

11  -7 

5-1 

4.2 

2.4 

144 

4 

4-8 

3-3 

32.0 

6 

7-5 

2.1 

8 

3-9 

4-7 

12 

14.4 

Error  Score 
of 

Normal  Group 

5-3 

5-3 

5-3 

5-3 

5-3 

5-3 

TABLE 60.  SCORE  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  DRAWING  TRI¬ 
ANGLES  WITH  THE  LEFT  HAND 


No.  of  Directed 
Trials  in  the 
Learning  Period 

Trial  upon  Which  the  Guided  Series  is  Introduced 

1 

3 

5 

7 

9 

11 

2 

12.7 

14.2 

5-3 

9.6 

14-3 

8.2 

4 

23.1 

23.6 

67.8 

6 

26.5 

9-7 

8 

41.3 

33-i 

12 

42.7 

Error  Score 

of 

5-3 

5-3 

5-3 

5.3 

5-3 

5-3 

Normal  Group 

THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


105 


TABLE 61.  SCORES  REPRESENTING  THE  INFLUENCE  OF  GUID¬ 
ANCE  UPON  THE  NUMBER  OF  ERRORS  MADE  IN  THE 
DISTRACTION  TEST  CHARACTERIZED  BY  DRAWING  TRI¬ 
ANGLES  WITH  THE  RIGHT  HAND,  WHILE  THE  LEFT 
HAND  TRAVERSES  THE  MAZE 


No.  of  Directed 


Trial  upon  Which  the  Guided  Series  is  Introduced 


Learning  Period 

1 

3 

5 

7 

9 

11 

2 

65.6 

19.3 

40.8 

8.7 

11  -3 

26.4 

4 

18.3 

40.4 

13.6 

6 

34-9 

4-4 

8 

24-3 

10.9 

12 

20.7 

Error  Score 

of 

9.6 

9.6 

9.6 

9.6 

9.6 

9.6 

Normal  Group 

VI 

GENERAL  SUMMARY 


The  discussion  of  the  present  chapter  contains  no  new  contribu¬ 
tion  to  the  material  of  the  investigation.  It  presents  briefly  the 
general  results  of  the  study  and  the  concepts  which  have  been  of 
value  in  the  systematization  of  the  facts.  The  hypotheses  are  sub¬ 
mitted  with  no  claim  for  their  completeness  as  explanatory  prin¬ 
ciples  for  the  phenomena  described,  nor  for  their  finality. 

i.  Influence  of  Control  upon  Learning 

A.  Factors  Influential  in  Determining  the  Effect  of  Control  upon 
Learning. 

1.  Type  of  problem :  The  present  investigation,  considered  in 
conjunction  with  that  reported  by  Carr  and  Koch,1  reveals  that 
the  effectiveness  of  guidance  is  a  function  of  the  type  of  problem 
in  which  it  is  employed.  Control  in  the  alternation  problem  was 
deleterious  in  its  effects,  generally  speaking,  although  there  were 
apparently  cases  of  great  individual  benefit.  In  the  maze  problem, 
on  the  contrary,  the  influence  of  control,  in  the  case  of  the  rats,  is 
very  beneficial.  The  two  problems  differ,  in  that  the  mastery  of 
the  maze  involves  primarily  the  elimination  of  excessive  move¬ 
ments,  whereas  in  the  alternation  problem,  the  acquisition  of  a  type 
of  response  quite  foreign  to  the  animal  constitutes  the  burden  of 
the  task. 

2.  Species  differences:  The  results  of  the  two  experiments  in 
which  men  and  animals  served  as  subjects  diverge  widely.  Wheth¬ 
er  this  divergence  is  dependent  wholly  upon  species  differences, 
upon  the  distribution  of  the  effort,  or  upon  other  uncontrolled 
factors  in  the  situations,  it  is  not  our  privilege  to  say.  We  have 
merely  the  fact  to  offer  that  the  control  was  very  efficacious  under 
the  conditions  maintained  in  the  experiment  conducted  upon  rats ; 

1  Op.  cit. 

106 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


io  7 


less  efficacious,  and  at  times  even  detrimental,  in  the  experiment 
upon  human  subjects. 

3.  Position  of  the  control :  In  the  case  of  the  animals,  the  de¬ 
gree  of  benefit  derived  from  control  administered  somewhere 
within  the  first  sixteen  trials,  varies  inversely  as  the  distance  of 
the  period  of  guidance  from  the  beginning  of  the  learning.  The 
efficacy  of  the  control,  in  the  case  of  the  human  subjects,  on  the 
other  hand,  tends  to  vary  directly  as  the  distance  (within  limits) 
of  the  series  of  guided  runs  from  the  initial  trial. 

4.  Amount  of  control :  The  efficacy  of  a  given  amount  of  guid¬ 
ance,  according  to  our  results,  is  a  function  of  the  period  in  the 
learning  process  at  which  the  directed  runs  are  interpolated.  The 
relative  influence  of  various  amounts  of  guidance,  furthermore, 
is  not  the  same  in  the  experiments  conducted  upon  human  and 
animal  subjects.  Hence,  no  broad  generalization  can  be  made 
concerning  the  optimum  number  of  directed  trials.  It  is  worthy  of 
note,  however,  that  the  relation  between  the  amount  and  the  ef¬ 
ficacy  of  the  control  is  no  simple  straight  line  relation.  The  modes 
of  functioning  of  the  control  are  many  and  often  antagonistic. 
Little  and  much  guidance  in  a  given  position,  for  instance,  may  be 
very  effective,  and  effective  in  like  degree,  whereas  a  medium 
amount  is  of  limited  value.  For  another  position,  there  may  be 
an  optimum  amount  of  control  which,  if  increased  or  decreased, 
causes  a  diminution  in  the  efficacy  of  the  guided  effort. 

B.  Possible  Modes  in  Which  the  Control  may  Function. 

1.  The  closing  of  the  blind  alleys  in  the  initial  stage  of  the 
learning  prevents  the  formation  of  habits  of  entering  cul-de-sacs 
at  a  time  when,  under  normal  conditions,  these  habits  are  most 
readily  acquired.  The  benefit  derived  from  this  particular  mode  of 
functioning  on  the  part  of  the  control  is,  probably,  greatest  in  the 
very  early  trials,  when  the  reaction  to  the  maze  situation  is  most 
diffuse,  and  is  much  reduced  as  soon  as  the  reaction  loses  its 
rambling  character.  It  is  possible  that  the  prevention  of  errors  ac¬ 
counts  in  large  measure  for  the  great  efficacy  of  initial  guidance 
in  the  case  of  the  rats  whose  learning  proceeds,  presumably,  on  a 
sensori-motor  level.  It  may  not  be  so  efficacious  in  its  influence 


io8 


HELEN  LOIS  KOCH 


upon  the  human  subjects  whose  learning  is  conceptual,  in  part  at 
least.  Learning  what  not  to  do  may  be  of  quite  as  much  value  to 
them  as  learning  what  to  do. 

2.  In  the  very  early  trials,  when  the  maze  path  is  unfamiliar 
and  retracings  abundant,  cul-de-sacs  may  act  as  barriers  and  pre¬ 
vent  returns  over  any  great  part  of  the  path.  Consequently,  one 
would  expect  the  blocking  of  the  blind  alleys  in  the  initial  stage 
of  the  learning  to  favor  long  retracings  and  a  resultant  high  error 
score.  Such  is  the  case  with  the  animals;  but  the  human  subjects, 
quite  contrarily,  make  fewer  return  errors  in  the  first  four  trials 
when  guided  than  when  uncontrolled. 

The  turns  in  the  true  path  of  the  small  stylus  maze  prevent  long 
returns  in  the  very  early  stages  of  the  learning.  The  simplification 
of  the  maze  pattern,  through  the  closing  off  of  the  blind  alleys,  also 
tends  to  decrease  the  retracings.  Hence,  in  the  early  runs,  the  guid¬ 
ed  groups  of  human  subjects  make  fewer  errors  than  does  the 
unguided  group.  As  soon,  however,  as  familiarity  with  the  path¬ 
way  is  attained  and  the  turns  no  longer  act  as  barriers,  a  tempo¬ 
rary  accentuation  of  the  retracing  habit  occurs,  just  as  it  did  in 
the  case  of  the  animals  in  the  early  trials. 

In  the  later  stages  of  the  learning,  when  the  tendency  to  retrace 
is  not  very  prominent,  except  as  it  is  prompted  by  entrances  into 
the  cul-de-sacs,  we  should  expect  the  prevention  of  cul-de-sac  er¬ 
rors  to  greatly  reduce  the  number  of  return  errors  made.  This  is 
probably  the  explanation  of  the  reduction  in  the  number  of  retrac¬ 
ings  which  characterizes  the  later  trials  of  the  long  periods  of 
either  initial  or  interpolated  control. 

The  increase  in  the  return  errors  accumulated  in  the  initial 
trials  of  a  period  of  interpolated  guidance  can  be  accounted  for  in 
terms  of  conflict  and  confusion.  The  introduction  of  the  con¬ 
trolling  device  alters  cues — especially  if  the  guidance  is  inter¬ 
polated  later  in  the  learning  period — upon  which  the  subject  has 
come  to  depend,  and  thus  temporarily  disrupts  the  reaction. 

3.  The  simplification  of  the  maze  pattern,  particularly  in  the 
initial  stages  of  the  learning,  may  react  upon  the  attitude  of  the 
subject  toward  the  problem.  Though  we  have  no  reason  to  doubt 
the  influence  of  attitudinal  factors  in  the  learning  of  the  animals, 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


109 


we  can  speculate  with  confidence  only  in  regard  to  their  reaction 
upon  the  human  subjects.  The  following  are  a  few  of  the  numer¬ 
ous  possible  ways  in  Which  the  control  may  influence  learning 
through  the  general  set  it  provokes.  The  relative  simplicity  of  the 
task  of  tracing  the  cul-de-sac-less  maze,  for  example,  may  estab¬ 
lish  confidence  on  the  part  of  the  subject  in  his  ability  to  master 
the  problem,  which  in  turn  may  increase  his  interest  and  serve  as  a 
goal  to  augment  his  effort.  It  is,  on  the  other  hand,  not  improbable 
that  confidence  will  lead  to  carelessness  or  non-plasticity  in  the 
post-control  period.  Confidence  established  in  the  period  of  con¬ 
trol  may,  moreover,  act  only  to  accentuate  the  discouragement 
which  often  attends  the  discovery  of  the  cul-de-sacs  in  the  post- 
control  period. 

It  is  not  our  intention  to  make  a  complete  catalogue  of  the 
particular  phase  of  the  control’s  influence  conditioned  by  the  set 
it  excites.  Concerning  the  method,  furthermore,  whereby  attitude 
influences  learning,  as  well  as  the  degree  to  which  the  attitude  is 
conditioned  by  the  manner  in  which  the  control  is  employed,  we 
have  no  constructive  suggestions  to  offer.  We  wish  merely  to  sug¬ 
gest  the  factor  as  one  that  must  be  reckoned  with  in  a  complete 
description  of  the  effect  of  guidance  upon  learning. 

4.  The  control,  to  the  extent  to  which  it  simplifies  the  maze  pat¬ 
tern,  may  facilitate  the  formation,  on  the  part  of  the  human  sub¬ 
ject,  of  an  accurate  concept  of  the  positional  relations  of  the 
various  parts  of  the  true  path.  This  mode  of  functioning  is,  pre¬ 
sumably,  influential  in  the  case  of  initial  and  interpolated  guidance 
and  increases  as  the  period  of  control  is  extended  up  to  a  certain 
point.  It  must  be  remembered,  however,  that  the  concept  formed 
during  the  longer  periods  of  initial  guidance  must  undergo  consid¬ 
erable  remodelling  when  the  subject  is  brought  in  contact  with  the 
cul-de-sacs  in  the  post-control  period.  If,  however,  the  control  is 
interpolated  later  in  the  learning,  it  may  facilitate  the  formation 
of  a  concept  which  includes  not  only  the  notion  of  what  is  the 
true  path,  but  what  is  the  false.  This  contrasting  of  the  true  path 
with  the  blind  alleys  through  the  aid  of  properly  interpolated 
guidance  may  be  one  of  the  reasons  why,  in  the  case  of  the  human 


IIO 


HELEN  LOIS  KOCH 


subjects,  the  efficacy  of  the  control  varies,  in  general,  directly  as 
the  distance  of  the  period  of  control  from  the  initial  trial. 

5.  Guidance,  whether  initial  or  interpolated,  may  act  to  facili¬ 
tate  the  substitution  of  proper  conceptual  as  well  as  sensory  stimuli 
for  releasing  the  desired  responses.  A  human  subject,  for  instance, 
may  readily  learn  that  catching  his  stylus  in  the  notches  in  the 
wall  produced  by  the  guiding  device,  is  not  necessary  and  that  the 
desired  forward  progress  is  made  if  he  follows  closely  the  opposite 
wall  or  runs  the  stylus  swiftly  down  the  path,  until  a  certain  turn 
is  reached.  The  elimination  of  the  habit  of  entering  a  cul-de-sac  is 
much  more  difficult  than  making  the  substitution  just  described. 
The  cul-de-sac  may  not  be  recognized  as  such  for  a  long  time. 
Even  if  the  character  of  the  blind  alley  is  known,  it  is  frequently 
difficult  to  overcome  the  tendency  to  make  a  slight  excursion  into 
the  mouth  of  the  alley  before  progressing  forward.  The  process 
of  overcoming  the  impulse  to  enter  the  cul-de-sac  is  often  in  its 
very  last  stages  similar  to  the  process  of  releasing  oneself  from 
dependence  upon  the  notch  as  a  cue  for  proceeding  forward. 

This  facilitation  of  the  formation  of  the  proper  reaction  to  a 
substituted  stimulus  which  is  not  conditioned  by  the  controlling 
device  is  a  factor  which,  presumably,  increases  as  the  amount  of 
control  is  increased.  One  would  expect  it  to  be  operative  in  the 
case  of  both  human  and  animal  subjects. 

6.  Interpolated  guidance  may  call  attention  to  cul-de-sacs  which 
were  not,  previous  to  the  period  of  control,  recognized  as  such. 
It  is  no  uncommon  occurrence  for  a  human  subject  to  enter  a  blind 
alley  regularly  for  a  long  time  without  being  aware  of  his  uneco¬ 
nomical  procedure.  Control,  though  limited  in  amount,  leads  to 
the  ready  elimination  of  such  an  error. 

7.  The  alteration  of  cues  attendant  upon  the  introduction  and 
removal  of  the  controlling  device  may  be  very  distracting.  If  the 
cues  have  been  thoroughly  integrated  into  the  subject’s  action  sys¬ 
tem,  the  alteration  of  them  may  entice  him  into  cul-de-sacs  and 
cause  much  vain  wandering.  Short  periods  of  initial  guidance  and 
control  interpolated  early  in  the  learning  period,  however,  do  not 
have  so  disturbing  a  subsequent  influence. 

The  alteration  of  cues  necessitates,  in  the  case  of  the  human  sub- 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE 


hi 


ject,  a  reorganization  of  his  concept  of  the  maze,  as  well  as  a 
reorganization  of  simple  kinaesthetic-  or  tactual-motor  habits. 
The  elimination,  for  example,  of  landmarks  such  as  the  notches  in 
the  wall  (as  the  entrances  to  the  blocked  alleys  are  known  to  the 
subjects)  may  disrupt  the  whole  sequence  of  reactions,  and  cause 
elaborate  analyses  of  the  difficulty.  The  subject  may  instigate  a 
systematic  search  for  the  lost  cues  which  are  never  to  be  recov¬ 
ered.  Long  wanderings  may  occur  which  afford  opportunity  for 
the  formation  of  many  undesirable  habits.  Such  a  type  of  response 
to  the  modifications  in  the  situation  one  might  expect  to  occur, 
when  the  period  of  control  has  been  rather  extended  and  the  cues 
from  the  guiding  device  explicitly  recognized. 

8.  Control,  if  considerable  in  amount,  and  especially  if  inter¬ 
polated  rather  late  in  the  learning,  may  result  in  the  formation  of 
two  types  of  reaction,  of  about  equal  strength,  to  a  particular  phase 
of  the  situation.  A  disrupting  conflict  of  habits  may  be  the  con¬ 
sequence.  One  would  expect  this  effect  of  control  to  be  greater  in 
the  case  of  the  animal  than  in  the  case  of  the  human  subjects. 

9.  The  simplification  of  the  task  during  the  period  of  control 
often  results,  if  the  number  of  guided  trials  has  been  large,  in  the 
establishment  of  a  rather  high  speed  set  which  prevails  throughout 
the  rest  of  the  learning. 

2.  Influence  of  Control  upon  Retention 

A.  Factors  Influential  in  Determining  the  Effect  of  Control  upon 
Retention. 

1.  Position  of  the  guided  effort:  Control  introduced  early  in 
the  learning  period  (within  the  first  six  trials)  is  an  aid  to  reten¬ 
tion,  whereas  that  occurring  in  the  latter  part  of  the  first  sixteen 
runs  is  unfavorable  in  its  influence.  The  degree  to  which  an  accu¬ 
rate  response  to  the  maze  situation  is  retained  varies,  generally 
speaking,  inversely  as  the  distance  from  the  initial  trial  in  the 
learning  period  at  which  the  controlled  runs  are  interpolated.  The 
reader  should  not,  however,  be  unmindful  of  the  fact  that  reten¬ 
tion  was  measured  by  the  number  of  errors  made  and  the  time  con¬ 
sumed  in  a  single  tracing  of  the  maze  forty-eight  hours  after  a 
mastery  of  the  problem  had  been  attained.  A  different  mode  of 


1 12 


HELEN  LOIS  KOCH 


measurement — that  of  relearning,  for  instance — or  a  considera¬ 
tion  of  the  results  at  a  different  stage  of  the  disintegration  of  the 
habit  might  not  reveal  the  existence  of  the  same  relations  between 
the  relative  degree  to  which  the  maze  habit  is  retained  by  the 
various  guided  groups. 

2.  Amount  of  guidance:  Barring  from  consideration  the  cases 
of  guidance  introduced  rather  late  in  the  learning  period,  we  ob¬ 
serve  that  the  accuracy  with  which  the  maze  habit  functions  after 
a  forty-eight-hour  interval  of  rest  varies  inversely  as  the  amount 
of  control  given,  whereas  the  speed  with  which  the  habit  runs 
itself  off  tends  to  vary  directly  as  the  number  of  directed  trials 
employed  in  the  learning.  No  consistent  relation  is  apparent  be¬ 
tween  the  degree  of  retention,  as  measured  either  in  terms  of  er¬ 
rors  or  time,  or  the  number  of  guided  runs,  when  these  are  inter¬ 
polated  rather  late  in  the  learning  period. 

B.  The  Relation  of  the  Influence  of  Guidance  upon  Learning  and 

Retention. 

The  correlation  between  the  influence  of  guidance  on  learning 
and  retention  is,  as  a  rule,  rather  small.  It  may  be  positive  or  nega¬ 
tive,  depending  on  the  number  and  position  of  the  guided  trials. 
A  small  amount  of  interpolated  guidance  usually  results  in  a  nega¬ 
tive  correlation.  Initial  guidance,  on  the  other  hand,  generally  pro¬ 
duces  a  positive  correlation.  The  size  of  the  correlation  between 
the  error  scores  of  the  learning  period  and  retention  test  increases 
as  the  amount  of  initial  guidance  is  increased,  whereas  the  correla¬ 
tion  between  the  time  consumed  in  the  learning  and  that  required 
in  the  retention  test  decreases  as  the  period  of  initial  guidance  is 
extended. 

C.  Possible  Modes  in  Which  Controlled  Learning  may  Influence 

Retention. 

i.  Control  in  the  learning  period  may  act  to  prevent  contact 
with  certain  error  situations.  The  reaction  of  this  mode  of  func¬ 
tioning  upon  the  retention  of  the  proper  habit  would  probably 
be  favorable.  The  usual  false  reactions,  whose  formation  in  the 
learning  period  the  control  prevented,  are  not  so  likely  to  occur 


THE  INFLUENCE  OF  MECHANICAL  GUIDANCE  113 

when  the  habit  functions  after  a  lapse  of  time,  as  they  would  had 
the  subject  frequently  indulged  in  them  and  eliminated  them  with 
effort.  This  reaction  of  controlled  learning  upon  retention  one 
would  expect  to  find  most  marked  in  those  groups  of  subjects 
whose  period  of  guidance  occurred  when  the  opportunities  for  the 
prevention  of  false  reactions  were  most  abundant;  namely,  in 
the  early  trials  of  the  learning  period. 

2.  Controlled  learning  may  lead  to  the  formation  of  conflict¬ 
ing  habits  in  response  to  certain  elements  of  the  maze  situation. 
The  proper  response  must,  to  be  sure,  attain  a  slight  dominance  in 
the  learning  period ;  but  after  the  habit  has  had  occasion  to  disin¬ 
tegrate  somewhat,  this  dominance  may  be  destroyed  and  the  con¬ 
flict  renewed  with  the  consequent  appearance  in  the  retention  test 
of  a  large  number  of  errors.  Such  a  mode  of  reaction  upon  reten¬ 
tion  would  be  most  prominent  when  the  period  of  controlled  learn¬ 
ing  has  been  rather  extended  or  has  occurred  late  in  the  acquisition 
of  the  maze  habit. 

3.  Influence  of  Control  upon  the  Adaptability 

of  the  Habit 

The  adaptability  of  the  maze  habit  formed  with  the  aid  of  guid¬ 
ance  is  conditioned  by  three  interrelated  factors;  namely,  the 
amount  of  guidance  given,  the  position  in  the  learning  period  at 
which  the  control  occurs,  and  the  nature  of  the  altered  situation 
to  which  the  habit  must  be  adjusted.  On  the  basis  of  our  results 
no  generally  applicable  statement  can  be  made  concerning  the  in¬ 
fluence  of  any  one  single  factor. 


* 


11.-1 


BF21.P96v.32 

Memory  defects  in  the  organic 


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